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A130089
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a(n) = denominator of Product_{k=1..n} k^mu(n+1-k), where mu(k) = A008683(k).
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3
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1, 1, 2, 3, 12, 20, 45, 14, 70, 864, 525, 880, 6237, 3328, 3003, 900, 25025, 60928, 53703, 19456, 3997125, 1209600, 3556553, 30912, 67643667, 11264000, 244375, 26687232, 52055003, 2702336, 351469125, 90272000, 47453715, 1284636672
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OFFSET
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1,3
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LINKS
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EXAMPLE
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a(5) = denominator(1^(-1)*2^(0)*3^(-1)*4^(-1)*5^(1)) = denominator(5/12) = 12.
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MAPLE
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with(numtheory): a:=n->denom(mul(k^mobius(n+1-k), k=1..n)): seq(a(n), n=1..41); # Emeric Deutsch, May 09 2007
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PROG
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(PARI) a(n) = denominator(prod(k=1, n, k^moebius(n+1-k))); \\ Michel Marcus, Feb 12 2019
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CROSSREFS
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KEYWORD
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frac,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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