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 A238717 #5 Mar 03 2014 15:51:38
%S A238717 3,41,8225,24171313,1017938927841,622602106165767361,
%T A238717 5608871461647356879321985,752730443089043674648784110740481,
%U A238717 1518229276131523691441191545330131883774977,46343219682310810626560369524452971573580502826086401
%N A238717 Sum_{k=0..n} C(2*k, k)^n.
%F A238717 a(n) ~ exp(-1/8) * 4^(n^2) / (Pi^(n/2) * n^(n/2)).
%t A238717 Table[Sum[Binomial[2*k,k]^n, {k, 0, n}], {n, 1, 20}]
%Y A238717 Cf. A211610, A211611.
%K A238717 nonn
%O A238717 1,1
%A A238717 _Vaclav Kotesovec_, Mar 03 2014