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A349920
Dirichlet g.f.: Product_{k>=2} (1 - mu(k)^2 * k^(-s)).
1
1, -1, -1, 0, -1, 0, -1, 0, 0, 0, -1, 1, -1, 0, 0, 0, -1, 1, -1, 1, 0, 0, -1, 0, 0, 0, 0, 1, -1, 1, -1, 0, 0, 0, 0, -1, -1, 0, 0, 0, -1, 1, -1, 1, 1, 0, -1, 0, 0, 1, 0, 1, -1, 0, 0, 0, 0, 0, -1, 0, -1, 0, 1, 0, 0, 1, -1, 1, 0, 1, -1, 0, -1, 0, 1, 1, 0, 1, -1, 0, 0, 0, -1, 0, 0, 0, 0, 0, -1, 0, 0, 1, 0, 0, 0, 0, -1, 1, 1, -1, -1
OFFSET
1
COMMENTS
Dirichlet inverse of A050320.
LINKS
FORMULA
a(1) = 1; a(n) = -Sum_{d|n, d < n} A050320(n/d) * a(d).
PROG
(PARI)
A050320(n, m=n) = if(1==n, 1, my(s=0); fordiv(n, d, if((d>1)&&(d<=m)&&issquarefree(d), s += A050320(n/d, d))); (s));
memoA349920 = Map();
A349920(n) = if(1==n, 1, my(v); if(mapisdefined(memoA349920, n, &v), v, v = -sumdiv(n, d, if(d<n, A050320(n/d)*A349920(d), 0)); mapput(memoA349920, n, v); (v))); \\ Antti Karttunen, Dec 05 2021
CROSSREFS
KEYWORD
sign
AUTHOR
Ilya Gutkovskiy, Dec 05 2021
STATUS
approved