Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #17 Jul 29 2015 15:31:04
%S 1,0,-1,0,-3,-6,-38,-186,-1181,-8094,-61865,-516702,-4688020,
%T -45887352,-481954769,-5406249972,-64506680939,-815807306442,
%U -10901200843386,-153475188129114,-2270769144678657,-35226976789341426,-571781884343282417,-9691701188493783546
%N Analog of A113869 for three generators.
%H Vaclav Kotesovec, <a href="/A114038/b114038.txt">Table of n, a(n) for n = 0..400</a>
%H John D. Dixon, <a href="http://www.combinatorics.org/Volume_12/Abstracts/v12i1r56.html">Asymptotics of Generating the Symmetric and Alternating Groups</a>, Electronic Journal of Combinatorics, Item R56 of Volume 12(1), 2005.
%F a(n) ~ -Pi * n^(n+1) / (2^(n+4) * exp(n) * (log(2))^(n+3/2)). - _Vaclav Kotesovec_, Jul 28 2015
%t nmax=30; A113871 = Rest[CoefficientList[Series[1/Sum[(k!)^2 x^k,{k,0,nmax}],{x,0,nmax}],x]]; Table[SeriesCoefficient[1 + Sum[A113871[[j]]/Product[n-i+1,{i,1,j}]^2,{j,1,nmax}],{n,Infinity,k}],{k,0,nmax}] (* _Vaclav Kotesovec_, Jul 28 2015 *)
%Y Related to A113871 in the same way that A113869 is related to A003319.
%K sign
%O 0,5
%A _N. J. A. Sloane_, Feb 01 2006
%E Missing a(3)=0 and more terms added by _Vaclav Kotesovec_, Jul 28 2015