%I #23 Sep 08 2022 08:46:10
%S 1,18,1810,263844,44916498,8345319268,1640651321764,335556407724360,
%T 70666388112940818,15220552520052960516,3337324864503769353060,
%U 742446552655157791828680,167167472732516775004539300,38021985442071415426063237704,8723111727436784830252513497928
%N a(n) = Sum_{k=0..2*n} binomial(2*n, k)^4.
%H G. C. Greubel, <a href="/A249332/b249332.txt">Table of n, a(n) for n = 0..100</a>
%F a(n) = A005260(2*n).
%t Table[Sum[Binomial[2*n, k]^4, {k, 0, 2*n}], {n, 0, 30}] (* _G. C. Greubel_, Aug 04 2018 *)
%o (PARI) {a(n) = sum(k=0, 2*n, binomial( 2*n, k)^4)};
%o (Magma) [(&+[Binomial(2*n,k)^4: k in [0..2*n]]): n in [0..30]]; // _G. C. Greubel_, Aug 04 2018
%Y Cf. A001448, A005260, A006480, A050984.
%K nonn
%O 0,2
%A _Michael Somos_, Oct 25 2014
|