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A339722
Dirichlet g.f.: Product_{k>=2} 1 / (1 + k^(-s))^7.
7
1, -7, -7, 21, -7, 42, -7, -42, 21, 42, -7, -105, -7, 42, 42, 84, -7, -105, -7, -105, 42, 42, -7, 189, 21, 42, -42, -105, -7, -203, -7, -175, 42, 42, 42, 217, -7, 42, 42, 189, -7, -203, -7, -105, -105, 42, -7, -399, 21, -105, 42, -105, -7, 189, 42, 189, 42, 42, -7, 385
OFFSET
1,2
FORMULA
a(1) = 1; a(n) = -Sum_{d|n, d < n} A339339(n/d) * a(d).
a(p^k) = A022602(k) for prime p.
KEYWORD
sign
AUTHOR
Ilya Gutkovskiy, Dec 14 2020
STATUS
approved