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%I #9 Jun 04 2017 16:23:12
%S 1,2,28,816,35960,2118760,156238908,13834413152,1429702652400,
%T 168899639028120,22451004309013280,3316276739861976176,
%U 538884034480519066248,95533608280955635872536,18348499272339029224271680,3795302872076181378439692480,841141456821158064519401490400,198852623925936212550698141090040,49949550731916384239220134110005024
%N a(n) = binomial(2*n^2, n).
%H G. C. Greubel, <a href="/A264411/b264411.txt">Table of n, a(n) for n = 0..300</a>
%F a(n) = Sum_{k=0..n} binomial(n^2, k) * binomial(n^2, n-k).
%F a(n) ~ (2*n)^(n-1/2) * exp(n-1/4) / sqrt(Pi). - _Vaclav Kotesovec_, Dec 01 2015
%t Table[Binomial[2*n^2,n], {n,0,15}] (* _Vaclav Kotesovec_, Dec 01 2015 *)
%o (PARI) {a(n)=binomial(2*n^2, n)}
%o for(n=0, 15, print1(a(n), " "))
%o (PARI) {a(n)=sum(k=0, n, binomial(n^2, k)*binomial(n^2, n-k))}
%o for(n=0, 15, print1(a(n), " "))
%K nonn
%O 0,2
%A _Paul D. Hanna_, Nov 26 2015
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