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A246699
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Squarefree n such that C(2^n - 1, n) is also squarefree, where C is the binomial coefficient.
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2
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1, 2, 3, 6, 11, 21, 29, 31, 51, 55, 57
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OFFSET
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1,2
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COMMENTS
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Conjectured to be finite.
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LINKS
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MATHEMATICA
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Select[Range[100], SquareFreeQ[#] && SquareFreeQ[Binomial[2^# - 1, #]] &] (* Vincenzo Librandi, Nov 14 2014 *)
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PROG
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(Magma) [n: n in [1..200] | IsSquarefree(n) and IsSquarefree(Binomial(2^n-1, n))];
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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