This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A185402 #14 Oct 23 2020 06:40:35
%S A185402 1,140,79380,62563200,57288340200,57169180452384,60324072262534080,
%T A185402 66193973824733314560,74770747698820830356700,
%U A185402 86365239335124673905181200,101541339191092781603799640464
%N A185402 a(n) = C(2n,n) * (7^n/n!^2) * Product_{k=0..n-1} (7k+2)*(7k+5).
%H A185402 G. C. Greubel, <a href="/A185402/b185402.txt">Table of n, a(n) for n = 0..320</a>
%F A185402 Self-convolution of A185401:
%F A185402 A185401(n) = (7^n/n!^2) * Product_{k=0..n-1} (14k+2)*(14k+5).
%F A185402 a(n) ~ cos(3*Pi/14) * 2^(2*n) * 7^(3*n) / (Pi*n)^(3/2). - _Vaclav Kotesovec_, Oct 23 2020
%e A185402 G.f.: A(x) = 1 + 140*x + 79380*x^2 + 62563200*x^3 +...
%e A185402 A(x)^(1/2) = 1 + 70*x + 37240*x^2 + 28674800*x^3 +...+ A185401(n)*x^n +...
%t A185402 Table[Binomial[2n,n] 7^n/(n!)^2 Product[(7k+2)(7k+5),{k,0,n-1}],{n,0,10}] (* _Harvey P. Dale_, May 10 2012 *)
%o A185402 (PARI) {a(n)=(2*n)!/n!^2*(7^n/n!^2)*prod(k=0,n-1,(7*k+2)*(7*k+5))}
%Y A185402 Cf. A184896, A185401, A185404.
%K A185402 nonn
%O A185402 0,2
%A A185402 _Paul D. Hanna_, Jan 26 2011