A062562 a(n) = Sum_{k=1..n} mu(k)*sigma(k).

0, 1, -2, -6, -6, -12, 0, -8, -8, -8, 10, -2, -2, -16, 8, 32, 32, 14, 14, -6, -6, 26, 62, 38, 38, 38, 80, 80, 80, 50, -22, -54, -54, -6, 48, 96, 96, 58, 118, 174, 174, 132, 36, -8, -8, -8, 64, 16, 16, 16, 16, 88, 88, 34, 34, 106, 106, 186, 276, 216, 216, 154, 250, 250, 250, 334, 190, 122, 122, 218, 74, 2, 2, -72, 42, 42, 42

Offset

0,3

Links

Table of n, a(n) for n=0..76.

Mathematica

Table[Sum[MoebiusMu[k]DivisorSigma[1, k], {k, n}], {n, 0, 80}] (* Harvey P. Dale, Nov 08 2011 *)

Prog

(PARI) s=[]; for(n=0, 130, s=concat(s, sum(k=1, n, moebius(k)*sigma(k)))); s

Crossrefs

Partial sums of A063441.

Sequence in context: A099027 A306925 A134466 * A208570 A106832 A129902

Adjacent sequences: A062559 A062560 A062561 * A062563 A062564 A062565

Keyword

sign

Author

Jason Earls, Jul 03 2001

Extensions

Corrected by Harvey P. Dale, Nov 08 2011

Status

approved