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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mohammad.h915
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Re: Problem 622

Post by mohammad.h915 » Wed Jun 05, 2019 7:27 am

Can you tell me the how many digits has answer?

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kenbrooker
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Re: Problem 622

Post by kenbrooker » Wed Jun 12, 2019 7:45 pm

Jochen_P wrote:
Mon Jan 07, 2019 7:47 am
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, ... but the decks in between are still a mistery [sic] to me.
"In between" well said; the minimum deck size is also conspicuous...
"Good Judgment comes from Experience;
Experience comes from Bad Judgment
..."
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mohammad.h915
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Re: Problem 622

Post by mohammad.h915 » Mon Jul 01, 2019 11:48 am

can help me and say what is the largest number that s(n) = 60

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