OFFSET
0,4
COMMENTS
What does this sequence count?
PROG
(PARI)
N=66; R=O('x^N); x='x+R;
F = 1; for (k=1, N+1, F = 1 + x / (1 - x * F * subst(F, 'x, -'x^2) ) + R; );
Vec(F)
CROSSREFS
KEYWORD
nonn
AUTHOR
Joerg Arndt, Feb 28 2014
STATUS
approved