A145168 G.f. A(x) satisfies A(x/A(x)^3) = 1/(1-x)^2.

1, 2, 15, 226, 4959, 136338, 4361818, 155947386, 6080986701, 254568183028, 11318103523886, 530301559146450, 26035289254487166, 1333502730683975402, 71012366873757289557, 3921010145962481940986, 223985973308662486807733

Offset: 0

Author

Paul D. Hanna, Oct 03 2008

Keywords

• nonn

Crossrefs

Cf. A145167, A145169, A145170 (A^3).

Programs

PARI

{a(n)=local(A=1+x+x*O(x^n),B);for(n=0,n,B=serreverse(x/A^3);A=1/(1-B)^2);polcoeff(A,n)}

Formula

Self-convolution square of A145167.

Self-convolution cube yields A145170.