OFFSET
0
EXAMPLE
G.f. = 1 - x^2 - x^4 + x^10 + x^14 - x^24 - x^30 + x^44 + x^52 - x^70 - ... - Altug Alkan, Mar 24 2018
MATHEMATICA
nmax = 100; CoefficientList[ Series[Product[(1 - x^(2*k)), {k, 1, nmax}], {x, 0, nmax}], x] (* Vaclav Kotesovec, Jul 05 2016 *)
PROG
(PARI) lista(nn) = {q='q+O('q^nn); Vec(eta(q^2))} \\ Altug Alkan, Mar 21 2018
CROSSREFS
KEYWORD
sign
AUTHOR
George Beck, Jul 03 2016
EXTENSIONS
Simpler definition from N. J. A. Sloane, Mar 24 2018
STATUS
approved