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A130089 a(n) = denominator of product{k=1 to 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; internal format)
OFFSET

1,3

EXAMPLE

a(5)=denom(1^(-1)*2^(0)*3^(-1)*4^(-1)*5^(1))=denom(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 (deutsch(AT)duke.poly.edu), May 09 2007

CROSSREFS

Cf. A130086, A130087, A130088.

Sequence in context: A100570 A056700 A140989 * A126292 A083265 A067391

Adjacent sequences:  A130086 A130087 A130088 * A130090 A130091 A130092

KEYWORD

frac,nonn

AUTHOR

Leroy Quet May 06 2007

EXTENSIONS

More terms from Emeric Deutsch (deutsch(AT)duke.poly.edu), May 09 2007

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Last modified February 17 10:57 EST 2012. Contains 206009 sequences.