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A339721
Dirichlet g.f.: Product_{k>=2} 1 / (1 + k^(-s))^6.
7
1, -6, -6, 15, -6, 30, -6, -26, 15, 30, -6, -60, -6, 30, 30, 51, -6, -60, -6, -60, 30, 30, -6, 96, 15, 30, -26, -60, -6, -114, -6, -102, 30, 30, 30, 96, -6, 30, 30, 96, -6, -114, -6, -60, -60, 30, -6, -210, 15, -60, 30, -60, -6, 96, 30, 96, 30, 30, -6, 156, -6, 30, -60, 172, 30
OFFSET
1,2
FORMULA
a(1) = 1; a(n) = -Sum_{d|n, d < n} A339338(n/d) * a(d).
a(p^k) = A022601(k) for prime p.
KEYWORD
sign
AUTHOR
Ilya Gutkovskiy, Dec 14 2020
STATUS
approved