OFFSET
0,5
FORMULA
O.g.f.: Sum_{n >= 0} (-1)^n * x^(n*(n+1)/2)/Product_{k = 1..n} ((1 + x)^k - x^k). Cf. A320591. - Peter Bala, Dec 22 2020
MATHEMATICA
m = 35; CoefficientList[Series[Product[1 - (x/(1+x))^k, {k, 1, m}], {x, 0, m}], x] (* Amiram Eldar, May 14 2021 *)
PROG
(PARI) N=66; x='x+O('x^N); Vec(prod(k=1, N, 1-(x/(1+x))^k))
CROSSREFS
KEYWORD
sign,easy
AUTHOR
Seiichi Manyama, Apr 14 2019
STATUS
approved