A195130 Series inversion of A100130.

1, 24, 852, 35744, 1645794, 80415216, 4094489992, 214888573248, 11542515402255, 631467591949480, 35063515239394764, 1971043639046131296, 111949770626330347638, 6414671157989386260432, 370360217892318010055832

Offset: 1

Author

Michael Somos, Sep 11 2011

Keywords

• nonn

Examples

			G.f. = q + 24*q^2 + 852*q^3 + 35744*q^4 + 1645794*q^5 + 80415216*q^6 + ...
		

Links

• Michael Somos, Table of n, a(n) for n = 1..16

Crossrefs

Cf. A005149, A100130.

Programs

Mathematica

a[ n_] := If[ n < 1, 0, SeriesCoefficient[ InverseSeries[ Series[ q / QPochhammer[ -q, q^2]^24, {q, 0, n}], q], {q, 0, n}]];

PARI

{a(n) = if( n<1, 0, polcoeff( serreverse( x * prod( k=1, n, 1 + (-x)^k, 1 + x * O(x^n) )^24), n))};

Formula

A005149(n) = -(-1)^n * a(n).