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A284315
Expansion of Product_{k>=0} (1 - x^(3*k+2)) in powers of x.
5
1, 0, -1, 0, 0, -1, 0, 1, -1, 0, 1, -1, 0, 2, -1, -1, 2, -1, -1, 3, -1, -2, 3, -1, -3, 4, 0, -4, 4, 0, -5, 5, 1, -7, 5, 2, -8, 6, 4, -10, 5, 5, -12, 6, 8, -14, 5, 10, -16, 5, 14, -19, 3, 17, -21, 2, 22, -23, -1, 26, -26, -3, 33, -28, -8, 38, -30, -12, 46, -32, -19
OFFSET
0,14
LINKS
FORMULA
a(n) = -(1/n) * Sum_{k=1..n} A078182(k) * a(n-k), a(0) = 1.
MATHEMATICA
CoefficientList[Series[Product[1 - x^(3k + 2), {k, 0, 100}], {x, 0, 100}], x] (* Indranil Ghosh, Mar 25 2017 *)
PROG
(PARI) Vec(prod(k=0, 100, 1 - x^(3*k+2)) + O(x^101)) \\ Indranil Ghosh, Mar 25 2017
CROSSREFS
Cf. Product_{k>=0} (1 - x^(m*k+m-1)): A081362 (m=2), this sequence (m=3), A284316 (m=4), A284317 (m=5).
Sequence in context: A218799 A078770 A072038 * A262928 A228429 A108316
KEYWORD
sign,look
AUTHOR
Seiichi Manyama, Mar 25 2017
STATUS
approved