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A232181
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First bisection of harmonic numbers (denominators).
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1
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1, 6, 60, 140, 2520, 27720, 360360, 360360, 12252240, 77597520, 5173168, 118982864, 8923714800, 80313433200, 2329089562800, 72201776446800, 13127595717600, 13127595717600, 485721041551200, 485721041551200, 19914562703599200, 122332313750680800
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OFFSET
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1,2
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COMMENTS
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Denominator of H(2n+1), where H(n) = sum_{k=1..n} 1/k.
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LINKS
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FORMULA
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a(n) ~ exp(2n).
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MATHEMATICA
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a[n_] := HarmonicNumber[2*n-1] // Denominator; Table[a[n], {n, 1, 25}]
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PROG
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(Magma) [Denominator(HarmonicNumber(2*n-1)): n in [1..30]]; // Bruno Berselli, Nov 20 2013
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CROSSREFS
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KEYWORD
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nonn,frac,easy
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AUTHOR
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STATUS
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approved
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