A262010 G.f. A(x) satisfies: A(x) = Sum_{n>=0} (4*n)!/(n!)^4 * x^n / A(x)^n.

1, 24, 1944, 215808, 27736920, 3879912960, 573515224128, 88128590118912, 13937449300517592, 2253641284021079040, 370887799310890842816, 61919951199385511890944, 10461342569407280971842240, 1785259939840128008227676160, 307282893462557980175918292480, 53283529423650333161886781538304, 9299430498554929711121662876725720

Offset

0,2

Comments

Self-convolution fourth power of A262013.

Links

Table of n, a(n) for n=0..16.

Formula

G.f.: x / Series_Reversion( Sum_{n>=0} (4*n)!/(n!)^4 * x^(n+1) ).

Example

G.f.: A(x) = 1 + 24*x + 1944*x^2 + 215808*x^3 + 27736920*x^4 + 3879912960*x^5 +...
such that
A(x) = 1 + 24*x/A(x) + 2520*x^2/A(x)^2 + 369600*x^3/A(x)^3 + 63063000*x^4/A(x)^4 + 11732745024*x^5/A(x)^5 +...+ (4*n)!/(n!)^4 * x^n/A(x)^n +...

Prog

(PARI) {a(n) = local(A); A = x/serreverse( x*sum(m=0, n, (4*m)!/(m!)^4*x^m +x*O(x^n)) ) ; polcoeff(A, n)}
for(n=0, 20, print1(a(n), ", "))

Crossrefs

Cf. A262013, A262012.

Sequence in context: A002671 A328126 A225220 * A267075 A263605 A327197

Adjacent sequences: A262007 A262008 A262009 * A262011 A262012 A262013

Keyword

nonn

Author

Paul D. Hanna, Sep 11 2015

Status

approved