A218032 G.f. A(x) satisfies A(x) = 1 + x / (1 - x * A(x^2)).

1, 1, 1, 1, 2, 3, 5, 8, 13, 21, 35, 57, 94, 154, 254, 417, 687, 1129, 1859, 3057, 5032, 8277, 13623, 22412, 36883, 60684, 99862, 164312, 270384, 444899, 732093, 1204629, 1982228, 3261701, 5367131, 8831505, 14532200, 23912499, 39347839, 64746320, 106539481, 175309363, 288469809

Offset: 0

Author

Joerg Arndt, Oct 19 2012

Keywords

• nonn

Comments

What does this sequence count?

Links

• Seiichi Manyama, Table of n, a(n) for n = 0..1000

Crossrefs

Cf. A319436, A349365.

Programs

PARI

N=66;  R=O('x^N);  x='x+R;
F = 1 + x;
for (k=1,N+1, F = 1 + x / (1 - x * subst(F,'x,'x^2) ) + R; );
Vec(F)