OFFSET
0,5
FORMULA
EXAMPLE
a(7) = 5 counts these partitions: 7, 43, 421, 4111, 1111111.
PROG
(PARI) my(N=60, x='x+O('x^N)); concat(0, Vec(sum(k=0, N, x^(3*k+1)/prod(j=1, 3*k+1, 1-x^j))))
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, May 20 2024
STATUS
approved