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A363775
Expansion of 1/(Sum_{k>=0} x^(k^2))^3.
1
1, -3, 6, -10, 12, -9, -2, 24, -54, 80, -84, 42, 66, -234, 420, -536, 450, -39, -740, 1770, -2688, 2898, -1722, -1320, 6078, -11349, 14736, -12992, 3084, 15999, -41212, 64032, -70788, 46020, 20778, -126132, 244120, -323421, 295410, -96848, -293868, 815829, -1297972
OFFSET
0,2
FORMULA
a(0) = 1; a(n) = -(3/n) * Sum_{k=1..n} A162552(k) * a(n-k).
PROG
(PARI) my(N=50, x='x+O('x^N)); Vec(1/sum(k=0, sqrtint(N), x^k^2)^3)
CROSSREFS
Convolution inverse of A002102.
Column k=3 of A363778.
Cf. A162552.
Sequence in context: A351828 A158975 A282876 * A261662 A345915 A050107
KEYWORD
sign,easy
AUTHOR
Seiichi Manyama, Jun 21 2023
STATUS
approved