Problem 622

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Oliver1978
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Problem 622

Post by Oliver1978 » Thu Apr 12, 2018 7:54 pm

From what I gather from the problem description, the outcome of s(n) is 0 if n is odd, else some value > 0. Is this right?
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hk
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Re: Problem 622

Post by hk » Thu Apr 12, 2018 8:01 pm

From the problem description:
Let $s(n)$ be the minimum number of consecutive riffle shuffles needed to restore a deck of size $n$ to its original configuration, where $n$ is a positive even number.
So if $n$ is odd $s(n)$ is not defined.
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Oliver1978
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Re: Problem 622

Post by Oliver1978 » Thu Apr 12, 2018 8:05 pm

Thanks :)
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Jochen_P
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Re: Problem 622

Post by Jochen_P » Mon Jan 07, 2019 7:47 am

Really interesting little problem (imho 15% is a bit low)
In the mean time I know exactly what the maximum deck size for s(n) = 60 is, or any other amount of shuffles for that matter, (No, you can't shuffle this deck by hand or even forklift :D ) but the decks in between are still a mistery to me.

You really could've asked for s(n)=31 :roll:
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