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A364257
Dirichlet inverse of A364255.
4
1, -2, -3, 0, -1, 6, -1, 0, 0, 2, -1, 0, -1, 2, 5, 0, -1, 0, -1, 0, 3, 2, -1, 0, -4, 2, 26, 0, -1, -10, -1, 0, 3, 2, -3, 0, -1, 2, 5, 0, -1, -6, -1, 0, -6, 2, -1, 0, 0, 8, 5, 0, -1, -52, -9, 0, 3, 2, -1, 0, -1, 2, 8, 0, 1, -6, -1, 0, 3, 6, -1, 0, -1, 2, 18, 0, -5, -10, -1, 0, -102, 2, -1, 0, -3, 2, 5, 0, -1, 12
OFFSET
1,2
FORMULA
a(1) = 1, and for n > 1, a(n) = -Sum_{d|n, d<n} A364255(n/d) * a(d).
PROG
(PARI)
\\ Needs also code from A364255:
memoA364257 = Map();
A364257(n) = if(1==n, 1, my(v); if(mapisdefined(memoA364257, n, &v), v, v = -sumdiv(n, d, if(d<n, A364255(n/d)*A364257(d), 0)); mapput(memoA364257, n, v); (v)));
CROSSREFS
Cf. A323239 (read modulo 2).
Sequence in context: A370505 A370507 A263230 * A366258 A319665 A004443
KEYWORD
sign
AUTHOR
Antti Karttunen, Jul 17 2023
STATUS
approved