Nice "Combinatorics"

by tastymath75025, Dec 19, 2016, 6:50 PM

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Is this problem NT or Combo?
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2015 ISL C3 wrote:
For a finite set $A$ of positive integers, a partition of $A$ into two disjoint nonempty subsets $A_1$ and $A_2$ is $\textit{good}$ if the least common multiple of the elements in $A_1$ is equal to the greatest common divisor of the elements in $A_2$. Determine the minimum value of $n$ such that there exists a set of $n$ positive integers with exactly $2015$ good partitions.

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Nice problem, thanks for including the motivation!

by shiningsunnyday, Dec 21, 2016, 10:44 AM

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well, I think we agree it's NT :P

by tastymath75025, Dec 22, 2016, 6:20 AM

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can’t we just say combinatorial nt

by cjquines0, Dec 23, 2016, 3:07 AM

To share with readers my favorite problem I came across today :) (Shout for contrib.)

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