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A373121
Expansion of B(x)^2, where B(x) is the g.f. of A230322.
0
1, 0, 2, -2, 1, -2, 1, 2, -2, 4, -6, 4, -4, 0, 5, -6, 13, -14, 9, -10, 1, 12, -16, 26, -32, 24, -19, 2, 22, -34, 57, -64, 48, -40, 4, 44, -70, 108, -124, 98, -73, 6, 79, -132, 205, -228, 181, -134, 13, 142, -245, 360, -404, 330, -230, 18, 241, -428, 630, -694, 567, -394, 35, 410, -735, 1054
OFFSET
0,3
FORMULA
G.f.: C(x) / D(x), where C(x) is the g.f. of A375148 and D(x) is the g.f. of A375149.
PROG
(PARI) my(N=70, x='x+O('x^N)); Vec(prod(k=1, N, (1-x^(7*k-3))*(1-x^(7*k-4))/((1-x^(7*k-2))*(1-x^(7*k-5))))^2)
CROSSREFS
KEYWORD
sign
AUTHOR
Seiichi Manyama, Aug 03 2024
STATUS
approved