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URL: https://oeis.org/A284317

⇱ A284317 - OEIS

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A284317
Expansion of Product_{k>=0} (1 - x^(5*k+4)) in powers of x.
7
1, 0, 0, 0, -1, 0, 0, 0, 0, -1, 0, 0, 0, 1, -1, 0, 0, 0, 1, -1, 0, 0, 0, 2, -1, 0, 0, -1, 2, -1, 0, 0, -1, 3, -1, 0, 0, -2, 3, -1, 0, 0, -3, 4, -1, 0, 1, -4, 4, -1, 0, 1, -5, 5, -1, 0, 2, -7, 5, -1, 0, 3, -8, 6, -1, 0, 5, -10, 6, -1, -1, 6, -12, 7, -1, -1, 9, -14
OFFSET
0,24
LINKS
FORMULA
a(n) = -(1/n)*Sum_{k=1..n} A284103(k)*a(n-k), a(0) = 1.
G.f. is the QPochhammer symbol (x^4;x^5)_infinity. - Robert Israel, Mar 27 2017
MAPLE
S:= series(mul(1-x^(5*k+4), k=0..200), x, 101):
seq(coeff(S, x, j), j=0..100); # Robert Israel, Mar 27 2017
MATHEMATICA
CoefficientList[Series[Product[1 - x^(5k + 4), {k, 0, 100}], {x, 0, 100}], x] (* Indranil Ghosh, Mar 25 2017 *)
PROG
(PARI) Vec(prod(k=0, 100, 1 - x^(5*k + 4)) + O(x^101)) \\ Indranil Ghosh, Mar 25 2017
CROSSREFS
Cf. Product_{k>=0} (1 - x^(m*k+m-1)): A081362 (m=2), A284315 (m=3), A284316 (m=4), this sequence (m=5).
Sequence in context: A164116 A164118 A180981 * A281243 A284314 A280454
KEYWORD
sign
AUTHOR
Seiichi Manyama, Mar 25 2017
STATUS
approved