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A354359
Dirichlet inverse of A124859.
6
1, -2, -2, -2, -2, 4, -2, -14, -2, 4, -2, 4, -2, 4, 4, -110, -2, 4, -2, 4, 4, 4, -2, 28, -2, 4, -14, 4, -2, -8, -2, -1526, 4, 4, 4, 4, -2, 4, 4, 28, -2, -8, -2, 4, 4, 4, -2, 220, -2, 4, 4, 4, -2, 28, 4, 28, 4, 4, -2, -8, -2, 4, 4, -20858, 4, -8, -2, 4, 4, -8, -2, 28, -2, 4, 4, 4, 4, -8, -2, 220, -110, 4, -2, -8
OFFSET
1,2
COMMENTS
Multiplicative because A124859 is.
LINKS
FORMULA
a(1) = 1, and for n > 1, a(n) = -Sum_{d|n, d < n} A124859(n/d) * a(d).
PROG
(PARI)
A124859(n) = { my(f=factor(n)); for(k=1, #f~, f[k, 1] = prod(j=1, f[k, 2], prime(j)); f[k, 2] = 1); factorback(f); }; \\ From A124859
memoA354359 = Map();
A354359(n) = if(1==n, 1, my(v); if(mapisdefined(memoA354359, n, &v), v, v = -sumdiv(n, d, if(d<n, A124859(n/d)*A354359(d), 0)); mapput(memoA354359, n, v); (v)));
CROSSREFS
KEYWORD
sign,mult
AUTHOR
Antti Karttunen, Jun 05 2022
STATUS
approved