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 A036687 #4 May 25 2020 16:04:20
%S A036687 1,12,420,35280,6486480,2473511040,1888413246720,2815188363187200,
%T A036687 8043859365429888000,43422645527382401280000,
%U A036687 437806134821131674998400000,8167684917019434265210752000000,279763767797866931083907001600000000,17478686582471797472931336490014720000000
%N A036687 a(n) = Product_{i=0..n} (3*i+1)! / (n+i)!.
%K A036687 nonn
%O A036687 0,2
%A A036687 Christian Krattenthaler (kratt(AT)ap.UniVie.AC.AT)