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 A134372 #11 Nov 16 2020 03:38:47
%S A134372 1,4,576,518400,1625702400,13168189440000,229442532802560000,
%T A134372 7600054456551997440000,437763136697395052544000000,
%U A134372 40990389067797283140009984000000,5919012181389927685417441689600000000
%N A134372 a(n) = ((2n)!)^2.
%F A134372 From _Amiram Eldar_, Nov 16 2020: (Start)
%F A134372 Sum_{n>=0} 1/a(n) = A334379.
%F A134372 Sum_{n>=0} (-1)^n/a(n) = A334632. (End)
%t A134372 Table[((2n)!)^(2), {n, 0, 10}]
%t A134372 ((2*Range[0,20])!)^2 (* _Harvey P. Dale_, Jul 14 2011 *)
%o A134372 (PARI) a(n) = ((2*n)!)^2; \\ _Michel Marcus_, Nov 16 2020
%Y A134372 Cf. A000142, A001044, A000442, A036740, A010050, A134366, A134367, A134368, A134369, A134371, A134374, A134375, A334379, A334632.
%K A134372 nonn
%O A134372 0,2
%A A134372 _Artur Jasinski_, Oct 22 2007