A130088 a(n) = numerator of Product_{k=1..n} k^mu(n+1-k), where mu(k) = A008683(k).

1, 2, 3, 2, 5, 3, 7, 1, 3, 25, 22, 21, 104, 21, 20, 11, 408, 585, 380, 55, 6272, 2431, 14904, 95, 176000, 25857, 1008, 149891, 356352, 10625, 510136, 35397, 7904, 224315, 35280, 776457, 118513664, 8265, 135200, 5425, 143972204544, 108150889

Offset: 1

Author

Leroy Quet, May 06 2007

Keywords

• frac
• nonn

Examples

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

Crossrefs

Cf. A130086, A130087, A130089.

Programs

Maple

with(numtheory): a:=n->numer(mul(k^mobius(n+1-k),k=1..n)): seq(a(n),n=1..50); # Emeric Deutsch, May 09 2007

PARI

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

Extensions

More terms from Emeric Deutsch, May 09 2007