OFFSET
1,6
COMMENTS
The justification for a(1) being 0 is that the sum is empty.
LINKS
EXAMPLE
12 = 2^3 * 3^1. So a(12) = mu(3) + mu(1) = -1 + 1 = 0.
PROG
(PARI) a(n)=local(v, i, s); v=factor(n); s=0; for(i=1, matsize(v)[1], s+=moebius(v[i, 2])); s \\ (Herrgesell)
(PARI) A112400(n) = vecsum(apply(e -> moebius(e), factorint(n)[, 2])); \\ Antti Karttunen, Jul 07 2017
CROSSREFS
KEYWORD
sign
AUTHOR
Leroy Quet, Dec 06 2005
EXTENSIONS
More terms from Lambert Herrgesell (zero815(AT)googlemail.com), Dec 09 2005
STATUS
approved