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A339706
Dirichlet g.f.: Product_{k>=2} (1 - k^(-s))^7.
7
1, -7, -7, 14, -7, 42, -7, 7, 14, 42, -7, -56, -7, 42, 42, -49, -7, -56, -7, -56, 42, 42, -7, -105, 14, 42, 7, -56, -7, -203, -7, 21, 42, 42, 42, -35, -7, 42, 42, -105, -7, -203, -7, -56, -56, 42, -7, 238, 14, -56, 42, -56, -7, -105, 42, -105, 42, 42, -7, 91, -7, 42, -56, 35, 42
OFFSET
1,2
FORMULA
a(1) = 1; a(n) = -Sum_{d|n, d < n} A339322(n/d) * a(d).
a(p^k) = A000730(k) for prime p.
KEYWORD
sign
AUTHOR
Ilya Gutkovskiy, Dec 13 2020
STATUS
approved