A358679 Dirichlet inverse of the characteristic function of A061345, odd prime powers.

1, 0, -1, 0, -1, 0, -1, 0, 0, 0, -1, 0, -1, 0, 2, 0, -1, 0, -1, 0, 2, 0, -1, 0, 0, 0, 0, 0, -1, 0, -1, 0, 2, 0, 2, 0, -1, 0, 2, 0, -1, 0, -1, 0, -1, 0, -1, 0, 0, 0, 2, 0, -1, 0, 2, 0, 2, 0, -1, 0, -1, 0, -1, 0, 2, 0, -1, 0, 2, 0, -1, 0, -1, 0, -1, 0, 2, 0, -1, 0, 0, 0, -1, 0, 2, 0, 2, 0, -1, 0, 2, 0, 2, 0, 2, 0, -1, 0, -1, 0, -1, 0, -1, 0, -6

Offset

1,15

Links

Antti Karttunen, Table of n, a(n) for n = 1..100000

Formula

a(1) = 1, and for n > 1, a(n) = -Sum_{d|n, d<n} A174275(n/d) * a(d).

Prog

(PARI)
A174275(n) = ((n%2)&&isprimepower(n));
memoA358679 = Map();
A358679(n) = if(1==n, 1, my(v); if(mapisdefined(memoA358679, n, &v), v, v = -sumdiv(n, d, if(d<n, A174275(n/d)*A358679(d), 0)); mapput(memoA358679, n, v); (v)));

Crossrefs

Cf. A061345, A174275.

Sequence in context: A140581 A137277 A039975 * A016253 A286998 A097796

Adjacent sequences: A358676 A358677 A358678 * A358680 A358681 A358682

Keyword

sign

Author

Antti Karttunen, Dec 23 2022

Status

approved