OFFSET
0,7
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..1000
FORMULA
G.f.: Sum_{k>=0} x^(4*k)/Product_{j=1..4*k} (1-x^j).
a(n) ~ A000041(n)/4. - Vaclav Kotesovec, May 21 2023
MAPLE
b:= proc(n, i) option remember; `if`(n=0, 1,
`if`(i<1, 0, b(n, i-1)+b(n-i, min(n-i, i))))
end:
a:= n-> add(b(n-4*i, min(n-4*i, 4*i)), i=0..n/4):
seq(a(n), n=0..60); # Alois P. Heinz, May 14 2023
PROG
(PARI) my(N=60, x='x+O('x^N)); Vec(sum(k=0, N, x^(4*k)/prod(j=1, 4*k, 1-x^j)))
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, May 14 2023
STATUS
approved