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A363800 Expansion of Product_{k>0} (1 - x^(7*k-5)) * (1 - x^(7*k-2)) * (1 - x^(7*k)). 2
1, 0, -1, 0, 0, -1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET
0
LINKS
FORMULA
G.f.: Sum_{k in Z} (-1)^k * x^(k * (7*k + 3) / 2).
a(0) = 1; a(n) = -(1/n) * Sum_{k=1..n} A363803(k) * a(n-k).
PROG
(PARI) my(N=100, x='x+O('x^N)); Vec(prod(k=1, N, 1-[1, 0, 1, 0, 0, 1, 0][k%7+1]*x^k))
CROSSREFS
Convolution inverse of A346797.
Sequence in context: A179560 A341602 A128407 * A134286 A023531 A320841
KEYWORD
sign
AUTHOR
Seiichi Manyama, Jun 23 2023
STATUS
approved

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Last modified August 14 09:50 EDT 2024. Contains 375159 sequences. (Running on oeis4.)