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A328731
Dirichlet g.f.: Product_{k>=2} 1 / (1 + k^(-s))^k.
2
1, -2, -3, -1, -5, 0, -7, -4, -3, 0, -11, 3, -13, 0, 0, 3, -17, 6, -19, 5, 0, 0, -23, 18, -10, 0, -10, 7, -29, 30, -31, -2, 0, 0, 0, 24, -37, 0, 0, 30, -41, 42, -43, 11, 15, 0, -47, 27, -21, 20, 0, 13, -53, 38, 0, 42, 0, 0, -59, 60, -61, 0, 21, 17, 0, 66, -67, 17, 0, 70
OFFSET
1,2
COMMENTS
Dirichlet inverse of A050368.
FORMULA
a(1) = 1; a(n) = -Sum_{d|n, d<n} A050368(n/d) * a(d).
CROSSREFS
Cf. A006881 (positions of 0's), A050368, A316441, A328730.
Sequence in context: A201737 A080063 A187680 * A140706 A200068 A139764
KEYWORD
sign
AUTHOR
Ilya Gutkovskiy, Oct 26 2019
STATUS
approved