two items from new Genii

Discuss the tricks and sleights which appear in Genii.

Postby gregg » 07/17/09 05:28 PM

The new work on the Gilbreath (sp) Principle in the new Genii is very interesting. A different patter line could be, "I invented a new card game. I can demonstrate it for you". At the end you can conclude, "Not only did I invent a new card game...but I also invented a way to cheat at it !". This way you can avoid the same-sex marriage patter.
The other feat that caught my imagination is Four Gone Conclusion and I worked on it quite awhile. I like HPC style 'moves' and to me this fell in that category. I felt the details on how to 'chuck' coins were a little sparse, but that didn't bother me since you have to play with this type of thing to get the knack, but now that I have I can offer this up; I found that you have to loft the three from your left BEFORE the 4th coin hits. This means that if you wait till the 4th hits and then 'chuck', you'll get an extra sound (1 is the 4th landing and the other when all 4 land in the right hand under card). So, 'chuck' the 3 early, and the 4th coin actually lands on the 3 coin stack in midair and then all land in the right hand under card and the left hand closes as if holding all 4.
Gregg Webb
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Postby Joe Mckay » 07/17/09 05:58 PM

I am obsessed with the Gilbreath Principle (and can't wait for the Max Maven book on it). However - I won't be able to pick up the latest copy of GENII until the middle of August. Any chance someone can give a rough idea of what to expect from this new work? New ideas in this area are very rare (and exciting). One of my favourite uses for this principle is the effect called 'Game Law' in the second volume of 'The Complete Walton'. It uses the Gilbreath Principle and allows the spectator to give the deck TWO riffle shuffles (as opposed to just one riffle shuffle - which is what happens in every other Gilbreath effect I have seen).

Joe
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Postby David Acer » 07/17/09 08:59 PM

gregg wrote: The new work on the Gilbreath (sp) Principle in the new Genii is very interesting. A different patter line could be, "I invented a new card game. I can demonstrate it for you". At the end you can conclude, "Not only did I invent a new card game...but I also invented a way to cheat at it !".


Along the same lines, I've been presenting the trick as a new kind of solitaire, then I offer to teach someone how to play. At the end, he or she gets however many points they get, and you clean up with a perfect score.
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Postby Joe Mckay » 07/18/09 07:33 AM

Oh - I already have access to this trick. I was confused by the reference to it being in the NEW issue of GENII. This effect can actually be found in the March issue of the magazine. Very nice it is too!

By the way - if anybody is interested in a brand new riffle shuffle principle, they should check out the following work from Leo Boudreau (who is one of the best thinkers in magic) - this was written up back in January of 2005...

www.themagiccafe.com/forums/viewtopic.p ... 6&forum=82

I have 'cut and pasted' the relevent information below:

--------------------------------------------

A popular misconception is that a shuffle is a good way of mixing cards. The truth is that a shuffle hardly mixes them at all and you can prove it to yourself.

Take a pack of Zener cards and stack them cyclically in 123451234512345... order from the top down, where 1=circle, 2=cross, 3=lines, 4=square and 5=star. Now separate the pack between any star and circle, preferable near the middle of the pack, and shuffle the two portions together using a genuine riffle shuffle. Immediately after the shuffle and without cutting the cards, deal yourself five cards face-down one at a time into a pile. Then turn the fifth card over so it lies face-up on top of the pile.

If the shuffle were any good at mixing the cards, the fifth card would reveal little information about the rest of the cards in the pile. But the truth is that, when the fifth card is either a circle or a square, the pile will contain two circles, a cross, a square and a line card. When the fifth card is either a cross or a line card, the pile will contain two circles, two crosses and a line card. When the fifth card is a star, the pile will contain one card of each design. So, the fifth card by itself can reveal the identities of all the other designs in the pile even after a legitimate shuffle. Check it out for yourself.

Anyone care to explain this curiosity? It gets curiouser.

Suppose a line design sits on top of the first pile, a circle on top of the second pile, a star on top of the third pile, a line design on the fourth pile and a star on the fifth pile. These top cards together with two values (X+1 and 6-X) will help you to calculate the designs in all the piles.

X is simply the design on the pile immediately before the pile you wish to calculate. For example, if you wish to calculate the designs in the fourth pile, the value of the star on the third pile, which is 5, means X=5.

FIRST STEP
The fourth pile must contain the designs X+1, X+2, ... right up through the design sitting on top of the pile. The top card of the fourth pile is a line card, which has a value of 3. So the fourth pile must contain the designs 6, 7 and 3. Numbers larger than 5 are reduced by 5, so 6 becomes 1 and 7 becomes 2. Thus, the fourth pile has a circle, a cross and a line design.

SECOND STEP
When the number of designs obtained in the FIRST STEP is less than five, then the pile will contain additional designs 6-X, 7-X, 8-X, ... up to the number necessary to produce five designs. In our example, the fourth pile must contain a second circle (6-5=1) and a second cross (7-5=2).

Here is another example: If you wish to calculate the designs in the second pile, the value of the lines on the first pile, which is 3, means X=3.

FIRST STEP
The top card of the second pile is a circle, which has a value of 1. So the second pile must contain the designs 4, 5 and 6, the latter reducing to 1. The corresponding designs are the square, star and circle. Since this step has produced only three designs, you must proceed to the next step to capture two more.

SECOND STEP
The second pile must also contain lines (6-3=3) and a second square (7-3=4)

Needless to say, the process will also work for playing cards. Stack them cyclically in A2345678910JQK... order from the top down in the face-down deck. Separate the deck at the center, between the King and Ace, and hand the two halves to a spectator for a genuine riffle shuffle. After the shuffle, he will deal thirteen cards face-down into a first pile, thirteen cards face-down into a second pile, and so on.

The thirteenth card, the one sitting on top of each pile, will now serve to identify the cards (values, not suits). The two-step process is the same here as for the Zener pack, except that now the formulas are X+1 and 14-X.

Suppose a 7 were on top of the first pile and a King were on top of the fourth pile. Your calculations for the first pile would proceed as follows: X=13, X+1=1, and 14-X=1. (Remember, numbers greater than 13 must be reduced by 13.)

FIRST STEP
Based on X+1, X+2, ..., the first pile must contain the Ace through 7.

SECOND STEP
Based on 14-X, 15-X, ..., the first pile must also contain a separate set of cards running from Ace through 6.

The process will also work for the suits if they are stacked cyclically in CHSD order from the top down in the face-down deck. Separate the deck between a Diamond and a Club somewhere near the center and hand the two halves to a spectator for a riffle shuffle. After the shuffle, he will deal four cards face-down into a first pile, four cards face-down into a second pile, and so on.

The fourth card, the one sitting on top of each pile, will now serve to identify the suits. The two-step process is the same, except that now the formulas are X+1 and 5-X.

Here is another riffle shuffle effect you may enjoy doing. It's called:

PRECOGNITION

You produce two decks of playing cards, separate one of the decks at its center and hand the two halves to a spectator for a genuine riffle shuffle. You keep the other deck which, you claim, has been arranged based on a dream you had the night before. Without shuffling your deck, you place it in your pocket and begin pulling cards out of your pocket and dealing them into a pile, turning them face-up one at a time. The spectator follows your lead, dealing the cards from his shuffled deck into a pile and turning face-up one at a time. Notice that you remove the cards first, followed by the spectator. Oddly enough, the cards dealt from both decks match perfectly, card after card.

PREPARATION

The first deck, deck A, is the one that will eventually go to the spectator. The second deck, deck B, is the one you will keep. Deck A must have a one-way back design. Shuffle it thoroughly so that the cards are truly in a random order. Then orient the backs of the first twenty-six cards so they all point one way and orient the bottom twenty-six cards so they all point the opposite way. Deck A is now ready.

Deck B is prepared next. Arrange it so it is in the exact same order as deck A. Then reverse the order of the twenty-six cards at the bottom of deck B. When done, the first twenty-six cards in both decks should be in the same order and the bottom twenty-six cards should be in reversed sequential order. Deck B is now ready. It will end up in your pocket.

PERFORMANCE

Separate deck A at the point where the back design changes from one orientation to the other. Hand both halves to the spectator for a genuine riffle shuffle. No cutting is permitted either before or after the shuffle unless the cut is false.

You will glance at the top card of the shuffled deck to see how it is oriented. If its orientation indicates that the card came from the top half of the spectator's deck, then remove the top card from deck B in your pocket and drop it face-up on the table. If, on the other hand, its orientation indicates that it came from the bottom half of his deck, then remove the bottom card from your deck. In either case, the spectator will then deal the top card from his deck face-up. The cards will match.

Note how the back of the next card in the spectator's deck is oriented. Use it to determine whether you should deal from the top or bottom of your deck. You will deal the appropriate card and the spectator will follow you by dealing his top card. Continue dealing in this manner and the cards in both decks will match perfectly. Keep the cards coming from your pocket as rapidly as you can and slap them down on the table.

-------------------------------------------

All the best, and congratulations to Leo on another amazing discovery!

Joe Mckay

PS. If Max Maven should read this - he mentioned he had a solution to a riffle shuffle problem (using cards with letters printed on the back - originally a Martin Gardner trick called 'SHUFFLED') in the bound reprint of AZIZ magazine (that was released along with IBIDEM Vol.3). I was just wondering if he would maybe release his solution in his future work on The Gilbreath Principle? I have worked on it myself, and would love to see what Max came up with as well...
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Postby David Acer » 07/18/09 09:11 AM

Joe Mckay wrote:Oh - I already have access to this trick. I was confused by the reference to it being in the NEW issue of GENII. This effect can actually be found in the March issue of the magazine. Very nice it is too!


Hi Joe,

You're referring to Dr. Giorgio Tarchini's "Fresh Gilbreath," but you'll be happy to hear that there is yet another new application for the principle, this time by Per Strandberg and Lennart Greene, which appears in the latest (August, 2009) issue.
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Postby Joe Mckay » 07/18/09 11:35 AM

That is great news! The Gilbreath Principle is the gift that keeps on giving...

Joe

PS. I only assumed the trick was the one from March since the table of contents for the August issue does not feature a MAGICANA section (if you click on the cover image at the front of this site you will see what I mean). Anyway keep up the great work David! I really enjoyed the multiple card control by Scott Robinson which was featured a couple of months ago...
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Postby Richard Kaufman » 07/18/09 12:59 PM

The installment of Magicana in the August issue was inadvertantly ommitted from the table of contents (and will be fixed online shortly).
Here it is:

Magicana (David Acer)
Double Stuff (Pete McCabe 18
Matchmaker (Per Strandberg) 19
Four Gone Conclusion (Jacky Kahan) 21
Real Life Nightshades (Dylan Gelinas) 21
Super Collectors (Doc Docherty) 22
Subscribe today to Genii Magazine
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Postby Jacky Kahan » 08/18/09 04:50 PM

Hello

If you want to "see" Four Gone Conclusion you can watch it HERE

Initially I named the move "the scoop move", Jeff Mcbride suggested to call it like that a few years back when I met him on a TV show in Turkey.

hope you'll like it

J
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Postby Ray Eden » 08/18/09 05:16 PM

Hey Jacky,

Do you have the vid on YouTube too? It can't be accessed unless one is on your friends list.

Ray
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Postby Jacky Kahan » 08/18/09 05:54 PM

oops...sorry,

I just unlocked it...

j
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Postby Jim Maloney » 08/18/09 06:38 PM

Jacky,
Would it be possible to post it somewhere more accessible? While you've opened it up so that the viewer doesn't need to be on your friends list, it still appears that you need a Facebook account to view it, which not everyone may have. (Shocking, I know!)

Looks pretty good, though!

-Jim
Books and Magazines for sale -- more than 200 items (Last updated January 10th, 2014. Link goes to public Google Doc.)
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Postby Jacky Kahan » 08/18/09 06:59 PM

ok...

here you have it on YOUTUBE

comments are welcome :)
j
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Postby David Acer » 08/19/09 09:54 PM

Jacky, what's the production you're doing in the clip?
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Postby Curtis Kam » 08/20/09 03:39 AM

Hey, that looks much better than I imagined after just reading it. Congratulations. I wouldn't have thought that the timing on the last coin would be consistent with the other tosses, but it was.

David, that looks like Danny Fleshman's rolling production.
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Postby Philippe Billot » 08/20/09 04:13 AM

Yes, in The Very Best, Yet!, page 1, Rollover Half Dollars (1990)
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Postby Jacky Kahan » 08/20/09 11:34 AM

Hello,

the production I do is Dan Fleshman's, but I thought Valarino also did it... not sure who's first?
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Postby David Acer » 08/29/09 06:27 PM

Jacky Kahan wrote:ok...

here you have it on YOUTUBE

comments are welcome :)
j


Hi Jacky,

Thanks for this! If you have time to post it, I'm sure people would also enjoy seeing your Spellbound move that ran in Genii a few years ago (it looks great).
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Postby Jacky Kahan » 09/02/09 06:46 PM

Here you have it: Spellboundless
Feedback is welcome :)
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Postby PerStr » 09/14/09 09:53 AM

Joe, thanks for posting the shuffling description!

After analyzing the shuffling of a 1..5 sequence, I made the following observations:
Top cards 1 and 4 can be treated the same, noted below as 1/4.
This also applies to top cards 2 and 3, noted below as 2/3.

All the changes from a straight 1..5 can then simply be
described in a table:
..........................Right Pile
...................1/4.......2/3..........5
..............._____________________________________
.........1/4..|............4=>2...........1=>5....
...............|
Left Pile 2/3.|...2=>4...................1=>5,2=>4
...............|
..........5....|...5=>1.....5=>1,4=>2...............
...............|


We have 1..5 (no pairs) if left and right top cards are from the same group (1/4,1/4),(2/3,2/3) and (5,5)
If we consider only cases other than 1..5, we have two cases with two pairs (2/3,5) and (5,2/3).
The remaining four cases will give one pair.


Noting that there will never be a pair of 3s, I have come up with the following sketch of a trick that may be of interest:

Setup:
1=AH (Love)
2=AC (Children, leaves on the tree of life)
3=AS (DEATH)
4=AD (Money,Diamonds)
5=J (Happiness,glee)

Note 2/3 is Black, 1/4 is Red

Use 5 - 10 sequences as above.
Show cards and ask for a spectator to have his fortune read.
Talk about the symbolic meaning and stress that a single symbol
means nothing, but all importance is on the pairing of symbols in a pile.
To create tension, point out that getting two AS in a pile would be terrible.

Cut between sequences and give the two packs to the volonteer to riffle together. "You have your fate in your own hands".

After shuffling and dealing the piles, turn the top cards face up.
Imagine an invisible pile with a J on top to the left of the first pile.

Now use your magical sensing abilities to scan the piles.
I can distinctly feel a pile getting hotter the more pairs it contains.

All consecutive piles with same color (R/R),(B,B), (J,J) have a right hand pile without any pairs. These right hand piles are pulled back towards you an inch.

All consecutive piles with a Black card and a Joker (B,J),(J,B) will contain two pairs in the right hand pile and the right hand piles are pushed an inch towards the spectator.

The rest of the piles will contain exactly one pair.

Call out your magical scanning results. Quickly show the no pair piles to verify your abilities.

Let the spectator go through the one pair line of piles, picking out the pair in the pile and putting it aside.

Finally, hoping to evade the dreaded death pair, let the spectator reveal the two pair piles (if there are any).

The sighs of relief are yor applause.

I did a quick test on my wife.
The first version, where I could tell the contents of the piles, evoked a yawn and a qoustion "OK, but what is the trick?"

The death pair version had her on edge,hardly dared to look through the fearful two pair pile.

If I have unknowingly used old ideas, I apologize.

per@LTPS.se
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Postby Tom Stone » 09/15/09 09:34 PM

PerStr wrote:All the changes from a straight 1..5 can then simply be
described in a table:

The table looks a bit odd. Did the forum software distort it?
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Postby PerStr » 09/17/09 08:00 AM

The preview showed that all spaces and tabs had been removed from the 3 x 3 matrix. I had to insert dots in order to make it almost readable.

I have written down my thoughts on Gilbreath tricks below, as there seems to be a lot of interest in this subject.
It is a little bit long, but I hope it is worthwhile to read it.


Some thoughts on Gilbreath tricks
Per Strandberg 2009-09-16


Part 1: Straight Gilbreath


Prologue:Open a new Bicycle deck of cards.
Remove jokers and extra cards.
Cut into two piles in the middle (between kings).
Riffle the piles together.
Deal 13 cards in a pile, repeat until 4 piles dealt.
Any pile will now be a 13-card straight.

Not much of a trick but a good illustration of the Gilbreath principle.

Definitions:In order to shorten the descriptions below, we need to define some terms and abbreviations.

Let S stand for an ordered collection of objects, in this case we will mostly use cards.
Let L (length of sequence S) be the number of objects in the collection.

Examples:
L=2 S={Red, Black}
L=4 S={Clubs, Hearts, Spades, Diamonds}
L=5 S={Ten, Jack, Queen, King, Ace}
L=13 S={A,2,3,4,.......Q,K}
L=26 S={A,B,C,D,E,F,...X,Y,Z}

If we repeat S N times, then we will get a total of N*L objects.
We will call N*L the size of the deck and call it D.


The Gilbreath Principle in seven steps:
Step one: Setup
Select the objects to be included in S.
Setup a deck by repeating S N times.
N is at least 2. (N=1 just tells you that if you reorganize the deck, you will still have all cards)

Example:
L=4 S={Clubs, Hearts, Spades, Diamonds}
N=13 gives a normal 52 card deck (D=52)


Step two: The Cut
Cut and complete the cut as many times as wanted (no cuts is also OK)
This will only permutate (shift around) the objects in S.
That is, we will still have the same objects but in another order.

Step three: The Split
Split the deck anywhere into two piles.

Step four: The Reversal
Reverse the order of the cards in one of the piles (Counting, pile turned face up)

Step five: The Shuffle
Shuffle the two piles together (Riffle shuffle, Rosette shuffle, random selection from top cards of either pile).

Step six: The Separation
Divide the shuffled deck into N groups with L cards.

Step seven: The Effect
All groups will contain the same objects as the starting set S (usually in a different order).



Example:

Now we use the prologue example with a deck in new-deck order.

Setup:
We have L=13 , S= {A,2...J,Q,K} , N=4, D=52

Cutting:
No cutting.

Split:
Split in the middle.

Reversal:
Not needed, as the last two suits are already reversed {K,Q,...2,A} compared to the pile with the first two suits.

Shuffle:
Riffle shuffle.

Separation:
Divide the deck into 13-card segments

Effect:
Each segment will be a 13 card straight when ordered {A,2,...J,Q,K}


That's it!
Now we can all try to find applications for this principle.
As input for ideas, I will describe a few of my favourite applications.
First I need to explain a very special shuffle.
Not having seen this before, I just call it the stair shuffle, lacking a better name.

Stair shuffle:
The strong feature of this shuffle in Gilbreath tricks is that it combines the split, reversal and shuffling,
which is done entirely by the spectator.

The spectator is told to take the top card and insert it halfway into the deck a few (zero, one, two or so) cards from the bottom.
The repeat this with the next top card inserted a few cards above the last inserted card.
When there is no more possible card insertion, the spectator squares the deck so that everybody can see that it is a genuine shuffle.


Applications:
The problem with a Gilbreath trick is to find an impressive use of the resulting unordered set.
One obvious use is poker tricks where a straight is important in any order.

Code lock:
There is a marketed trick called Wordlock.
For different reasons I prefer to use the actual padlock but as a Gilbreath trick instead of the marketed version.
The padlock is a code lock with 5 rings with letters instead of digits.

I use blank cards and write letters on them.
L=5 S={ B,R,A,I,N}
N=10 gives a 50 card deck.
I use two ordinary normal cards and do a nonsense prediction that fails but gives me the opportunity to show two cards
to reinforce the impression of a normal deck.

I deal 20 cards in a pile, giving some nonsense reason.
The spectator now have a choice: small pile (20 cards, reversed), large pile (30 cards, not reversed) or both piles.
Small pile: Stair shuffle
Big pile: Stair shuffle
Both piles: Riffle shuffle
The shuffle is performed by the spectator.

The spectator now deals 5-card piles and can stop after a dealt pile or deal all cards and select a pile.
Hopefully there will be a big surprise when the pile is revealed to contain 5 letters.
"Use your head to find the secret word" will lead quickly to BRAIN, which will open the padlock.

The routine is based on accidentally locking a ring in the padlock and needing magical help from a spectator to retrieve the ring

The very special deck can also be used with the name BRIAN (birthdays etc.), but most often I have to buy a blank deck to personalize tricks.

Love thermometer:
Specially suited for weddings.
Jumbo cards.
A special stand long enough for 13 jumbo cards.
The stand has marked slots for Ace to King.

Presented as a love test.
Love is proportional to longest run of cards in sequence.
"Normal is 5 - 7. Below that, you should worry about your situation.
However, 8-10 is a reason for congratulations.
11-13 are reserved for matches made in heaven"
This makes the bridal pair very interested in the result.
.
L=13 S={A,2...Q,K in random order} with a 13-character message in big letters on the back of the cards, Ace first character, King last character.
Messages usually names of bride and groom.
If possible, use one or two spaces in the message and order S so that the spaces come first.
That way you can flash the backs of one or two cards when you bring out the deck.
This trick is done face up.
Bride cuts.
Groom stair shuffles.
Groom deals into four 13-card piles.
Bride selects one pile.
Groom orders them in the stand from A to K.
Bridal pair nervously seeing the gaps between runs of cards diminishing.
Audience starting to notice the letters and see a message being completed by the groom.
When the last card fills the last gap, the bridal pair smile happily and relieved.
If the audience manages to not disclose the text on the backs of the cards, the bridal pair will have a big surprise when the stand is turned around.


Bridge hand:

Use 4 ordered decks.
Take the spades from each deck and put into a card case.
Put one of the 3-suit decks in your pocket as well.

Talk about bridge and what is the best possible hand.
Open case and bring out all-spade deck.
Let spectator cut.
Let spectator do the stair shuffle, deal 4 13-card piles and select one pile.
Collect the other three piles and put back in the case.
Put the case to the side.
Now ask the spectator to pick up the pile and order suits and values the way he prefers.
Take the 3-suit deck from your pocket when spectator picks up the pile.
When he has sorted and puts the cards down on the table, switch decks, as all eyes will be on the cards.

When the excitement about a 13 spades hand has died out, there is usually a demand to see the rest of the deck.
For laymen I show the other 3 suits in order and this is another miracle.
For magicians, I show a shuffled deck without spades, otherwise it is too impossible and arouses the thought of a deck switch.
If nobody asks, you just open the case, spread the 3 suits next to the spades and, without further comments, assemble the complete deck again
and go ahead with a new trick with the deck.




Part 2: Gilbreath Pairs.

When can two consecutive cards in a Gilbreath shuffled deck make a pair?
From the preceding section we know that the first L cards will contain all the L objects in S.
Thus we cannot have two copies of an object among the group of L cards.
The same applies to the next group of L cards.

Conclusions:
If there are two consecutive cards, these must be the last card of a group of L cards and the first card in the next group of L cards,
as there cannot be any pairs within a group.

If the last card of the first group and the first card in the next group were taken from the same pile (Reversed pile or non-reversed pile),
then there would not be a pair as the cards would be the last and the first object in S.

The only possibility is when the two cards come from different piles.

What is not so obvious is that this is also a sufficient condition.

Pair principle:
In a Gilbreath shuffled deck there will be two consecutive cards with the same object if and only if the two cards are the last card in a group of
L cards and the first card in the next group of L cards AND one card is taken from the reversed pile and the other card from the non-reversed pile.


Time for an example:

L=4, N=2*3, S={C,H,S,D}
Order 12 cards from a red deck in CHaSeD order in a pile.
Order 12 cards from a blue deck in CHaSeD order in a pile.

Reverse the blue pile.

Shuffle by randomly selecting cards from either pile.

Select 3 cards, check for suited pairs.
Turn over the top cards in both piles (Showing card number L and L+1).
Check that it will show a suited pair.

Select 2 cards (L+2, L+3)
Turn over the top cards in both piles (Showing card number 2L and 2L+1).
Check that it will show a suited pair.

Select 2 cards (2L+2, 2L+3)
Turn over the top cards in both piles (Showing card number 3L and 3L+1).
Check that it will show a suited pair.

Repeat...

Offset:
The asymmetry for the first pair is annoying.
It would be better to always select the same number of cards before getting the pair on top.

This is achieved by introducing an offset by one in one of the piles.
This means transferring the top card in a pile to the bottom of the same pile.
This will shift the pair position to L-1 and L, i.e. e. the two last cards in a group of L cards is the possible pair position.

Example again:

Same setup as in the last example.
Do the offset after reversing.

Riffle shuffle the red and blue pile together.
Deal two cards: No suited pair ( Cards 1 and 2)
Deal two cards again: Suited pair if backs are red and blue (Cards 3 = L-1 and 4=L), else no suited pair
There is a 50% chance for a pair if randomly shuffled.

We can now describe the pair production:


The Gilbreath Pair Principle in seven steps:

Step one: Setup (same as before)
Select the objects to be included in S.
Setup a deck by repeating S N times.


Step two: The Cut (same as before)
Cut and complete the cut as many times as wanted (no cuts is also OK)

Step three: The Split (New restriction)
Split the deck BETWEEN two sequences (at L,2L,3L...) into two piles.

Step four: The Reversal AND Offset (Offset added)

Reverse the order of the cards in one of the piles (Counting, pile turned face up)
MOVE ONE CARD FROM TOP TO BOTTOM IN ONE OF THE PILES.

Step five: The Shuffle (same as before)
Shuffle the two piles together (Riffle shuffle, Rosette shuffle, random selection from top cards of either pile).

Step six: The Separation (same as before)
Divide the shuffled deck into N groups with L cards.

Step seven: The Effect (new effect)
All groups will have a pair as the last two cards if the cards come from different piles.



Applications:

This principle with L=4 is the basis for Lennart Greens Matchmaker.

I use it for a similar routine based on an idea by Tom Stone.

Marriage fortune telling:
I use kings and queens from 4 - 6 decks.
I have stacked the kings in CHaSeD order and the queens in the same order, but offset by one.
Then I riffle the packets together and add the four aces on top.

Offer four couples to participate in the fortune telling.
Let each couple draw an ace to determine their particular suit.
Showing a mixture of Ks and Qs, I openly pick out the Qs in a pile, preserving the stacked order.
The remaining Ks are turned face up (doing the reversing).
I then shuffle the Ks and Qs together. "Inserting the queens into the kings" or the other way around,
depending on audience.

"Fate has now determined your futures".
Dedicate part of the table as "The Divorce Section" and the other part as "The Bliss Section".
Deal pairs of cards to alternating sections.
Remember to start in the Divorce section.

"The only thing that matters are pairs with a K/Q with the same suit, your suit!"
Remove all face down pairs (Q/Q) and all face up pairs (K/K).

Start turning over the Qs in the Bliss section, where all pairs will be suited and everybody happy.
Talk about the severity of having a suited pair the Divorce section.
Turn over the Qs and, magically, no destroyed marriages!


Poker wager:

Setup:
L=13 S={A..K in random order}

Pre-reverse and offset second half.
False shuffle and cut in the middle (crimp) into two face down piles..

"Game is the simplest possible. ONLY pairs count. Best of three wins".
"Pick five cards. If you get a pair, you win"
Your opponent will not win.
"OK. I will give you another chance. Pick another five cards".
Still no pair.
"To give you better odds, I can only use the top cards.
But first, I give you the opportunity to remove a burn card from one of the piles".
That done, you turn over the top cards and show a pair.

Repeat a second time.
You will then lead by 2 - 0.

Last round:
After picking the five cards, allow your opponent to keep them and add another five cards.
Still no pair.
Let him add the burn card so that he now has eleven cards but still no pair.
Turn over the top cards and you win by 3-0.

Other possibilities:
I have used colored balls and colored boxes and flags to make trick versions of give-away shows seen on TV.
This variation of Gilbreath tricks can be of use to create new tricks, at least it has been for me, as it is not so well known
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Postby Richard Kaufman » 09/17/09 09:57 AM

Thanks, Per, for your generositity in releasing more of your intriguing work on the Gilbreath Principle here!
Subscribe today to Genii Magazine
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Postby Joe Mckay » 09/17/09 12:49 PM

I'll add my thanks for the generous gift from Per. Thanks! I am going to print off your ideas and study them this weekend...

By the way - anyone who is interested in the Leo Boudreau principle should check out the following link. It features some interesting analysis from Colm Mulcahy:

THE BLIGREATH PRINCIPLE

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