A174942 a(n) = Sum_{k<=n} A007955(k) * A008683(n-k+1) = Sum_{k<=n} A007955(k) * mu(n-k+1), where A007955(m) = product of divisors of m.

1, 1, 0, 3, -7, 22, -36, 14, -44, -29, -91, 1525, -1692, -1686, 109, -1246, 534, 2818, -5769, 1034, -5042, -16561, 5185, 315777, -321633, -338860, 5749, -319896, 318256, 441483

Offset

1,4

Links

Table of n, a(n) for n=1..30.

Example

For n = 4, A007955(n) = b(n): a(4) = b(1)*mu(4) + b(2)*mu(3) + b(3)* mu(2) + b(4)*mu(1) = 1*0 + 2*(-1) + 3*(-1) + 8*1 = 3.

Crossrefs

Sequence in context: A177820 A174230 A158236 * A128599 A182174 A080882

Adjacent sequences: A174939 A174940 A174941 * A174943 A174944 A174945

Keyword

sign

Author

Jaroslav Krizek, Apr 02 2010

Status

approved