A172403 G.f.: 1/(1-x) = Sum_{n>=0} a(n)*x^n/(1+x)^(2^(n+2)-4).

1, 1, 5, 51, 1059, 44620, 3795202, 649054326, 222639357434, 152968659433948, 210361428050679489, 578800452225641673965, 3185715127946958245708501, 35071788327149162320178667272, 772254422082165524711277630023576

Offset

0,3

Links

Table of n, a(n) for n=0..14.

Formula

Column 2 of triangle A172400.

Example

1/(1-x) = 1 + x/(1+x)^4 + 5*x^2/(1+x)^12 + 51*x^3/(1+x)^28 + 1059*x^4/(1+x)^60 +...

Prog

(PARI) {a(n)=if(n==0, 1, polcoeff(-(1-x)*sum(m=0, n-1, a(m)*x^m/(1+x +x*O(x^n))^(2^(m+2)-4)), n))}

Crossrefs

Cf. A172400, A172401, A172402.

Sequence in context: A124559 A368838 A348023 * A022516 A003515 A022501

Adjacent sequences: A172400 A172401 A172402 * A172404 A172405 A172406

Keyword

nonn

Author

Paul D. Hanna, Feb 01 2010

Status

approved