OFFSET
0,6
FORMULA
G.f.: Product_{k>0} (1-x^(5*k-2)) * (1-x^(5*k-3)) / (1-x^(5*k))^2.
PROG
(PARI) my(N=60, x='x+O('x^N)); Vec(1/sum(k=-N, N, x^(3*k)/(1-x^(5*k+1))))
(PARI) my(N=60, x='x+O('x^N)); Vec(prod(k=1, N, (1-x^(5*k-2))*(1-x^(5*k-3))/(1-x^(5*k))^2))
CROSSREFS
KEYWORD
sign
AUTHOR
Seiichi Manyama, Jul 29 2024
STATUS
approved