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A135760
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Least number in A001764 divisible by 3^n: a(n) = A001764(3^n-1).
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0
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OFFSET
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0,2
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COMMENTS
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Only numbers in A001764 not divisible by 3 are: A001764((3^n-1)/2) for n>=0.
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LINKS
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FORMULA
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a(n) = C(3^(n+1)-3, 3^n-1) / (2*3^n-1).
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MATHEMATICA
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Table[Binomial[3^(n + 1) - 3, 3^n - 1]/(2*3^n - 1), {n, 0, 10}] (* G. C. Greubel, Nov 07 2016 *)
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PROG
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(PARI) a(n)=binomial(3^(n+1)-3, 3^n-1)/(2*3^n-1)
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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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