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A114648
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Number of occurrences of 6 as a denominator in Bernoulli(k) for 0<=k<=10^n.
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2
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0, 1, 10, 87, 834, 7992, 77696, 758582, 7436825, 73129588, 720726912
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OFFSET
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0,3
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LINKS
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MATHEMATICA
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DenominatorBernoulliBQ[n_Integer, denom_Integer] := If[EvenQ[n], Times @@ Select[Divisors[n] + 1, PrimeQ] == denom, 1 + KroneckerDelta[n, 1] == denom]; A114648[n_] := A114648[n] = Length[Select[Range[10^n], DenominatorBernoulliBQ[#, 6] &]] (* Enrique Pérez Herrero, Aug 01 2010 *)
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CROSSREFS
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KEYWORD
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nonn,hard
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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