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