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A319244
Expansion of Product_{k>0} (1 - x^(k^3))/(1 + x^(k^3)).
1
1, -2, 2, -2, 2, -2, 2, -2, 0, 2, -2, 2, -2, 2, -2, 2, 0, -2, 2, -2, 2, -2, 2, -2, 0, 2, -2, 0, 2, -2, 2, -2, 4, -6, 6, -2, -2, 2, -2, 2, -4, 6, -6, 2, 2, -2, 2, -2, 4, -6, 6, -2, -2, 2, 0, -2, 0, 2, -2, -2, 6, -6, 2, 2, -2, 2, -2, 6, -10, 10, -6, 2, 0, -2, 2, -6, 10
OFFSET
0,2
FORMULA
Convolution inverse of A280263.
MATHEMATICA
CoefficientList[Series[Product[(1-x^(k^3))/(1+x^(k^3)), {k, 10}], {x, 0, 80}], x] (* Harvey P. Dale, Nov 10 2024 *)
CROSSREFS
Product_{k>0} (1 - x^(k^m))/(1 + x^(k^m)): A002448 (m=1), A319243 (m=2), this sequence (m=3).
Cf. A280263.
Sequence in context: A044925 A376680 A323356 * A309286 A102671 A292519
KEYWORD
sign
AUTHOR
Seiichi Manyama, Sep 15 2018
STATUS
approved