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A130089 a(n) = denominator of Product_{k=1..n} k^mu(n+1-k), where mu(k) = A008683(k). 3
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..34.

EXAMPLE

a(5) = denominator(1^(-1)*2^(0)*3^(-1)*4^(-1)*5^(1)) = denominator(5/12) = 12.

MAPLE

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

PROG

(PARI) a(n) = denominator(prod(k=1, n, k^moebius(n+1-k))); \\ Michel Marcus, Feb 12 2019

CROSSREFS

Cf. A130086, A130087, A130088.

Sequence in context: A140989 A281086 A355847 * A323119 A307035 A319404

Adjacent sequences:  A130086 A130087 A130088 * A130090 A130091 A130092

KEYWORD

frac,nonn

AUTHOR

Leroy Quet, May 06 2007

EXTENSIONS

More terms from Emeric Deutsch, May 09 2007

STATUS

approved

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Last modified October 6 15:15 EDT 2022. Contains 357269 sequences. (Running on oeis4.)