A135869 G.f. A(x) = 1 + x*A(3x)^2.

1, 1, 6, 117, 6642, 1097874, 537135948, 784812995973, 3435153688724346, 45086429284345043334, 1775007791598340247784372, 209630197234751724563143145346, 74271350069687203431923556331222068

Offset: 0

Author

Paul D. Hanna, Dec 02 2007

Keywords

• nonn

Comments

Self-convolution equals A135870.

Crossrefs

Cf. A135867, A135870.

Programs

PARI

{a(n)=local(A=1+x+x*O(x^n));for(i=0,n,A=1+x*subst(A,x,3*x)^2);polcoeff(A,n)}