A238430 Expansion of F(x) where F(x) = 1 + x / (1 - x / F(-x^2) ).

1, 1, 1, 1, 2, 3, 4, 6, 9, 13, 18, 26, 38, 54, 77, 111, 160, 229, 328, 472, 678, 972, 1396, 2006, 2880, 4134, 5937, 8527, 12242, 17577, 25242, 36246, 52043, 74729, 107308, 154084, 221246, 317692, 456182, 655032, 940564, 1350572, 1939304, 2784660, 3998522, 5741532, 8244326, 11838106, 16998472, 24408302

Offset

0,5

Comments

What does this sequence count?

a(n+1)/a(n) tends to 1.4359108952505909... - Vaclav Kotesovec, Feb 28 2014

Links

Table of n, a(n) for n=0..49.

Prog

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

Crossrefs

Sequence in context: A303667 A050811 A076968 * A285484 A098889 A061481

Adjacent sequences: A238427 A238428 A238429 * A238431 A238432 A238433

Keyword

nonn

Author

Joerg Arndt, Feb 28 2014

Status

approved