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A297054
The coefficients of the product (1-x^2)(1-x^3)(1-x^4)... / (1+x).
0
1, -1, 0, -1, 0, 0, 0, 1, 0, 1, 0, 1, -1, 1, -1, 0, -1, 0, -1, 0, -1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, -1, 1, -1, 1, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, -1, 1, -1, 1, -1, 1, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0
OFFSET
1
MATHEMATICA
iend = 100;
s = Series[1/(1 + x) Product[(1 - x^i), {i, 2, iend}], {x, 0, iend}];
Print[s]; Print[CoefficientList[s, x]]
PROG
(PARI) first(n) = Vec(prod(i=2, n-1, 1 - x^i)/(1 + x) + O(x^n)) \\ Iain Fox, Dec 24 2017
CROSSREFS
Sequence in context: A379274 A321512 A373489 * A359349 A266459 A354199
KEYWORD
sign
AUTHOR
David S. Newman, Dec 24 2017
STATUS
approved