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 A123312 #7 Jan 13 2025 04:10:27 %S A123312 1,1,6,84,2010,70596,3331006,199417056,14559631506,1259526351000, %T A123312 126308710634414,14434568970310656,1854260500658184762, %U A123312 264771440776810595320,41635233706865669566110 %N A123312 a(n) = A123311(n)/(n+1), where A123311 forms the central terms of triangle A123305. %C A123312 Triangle T=A123305 is defined by: (column k of T) = (k+1)*(column k of T^2) shifted to have an initial '1'; thus a(n) = A123311(n)/(n+1) is an integer for n>=0. %Y A123312 Cf. A123305; A123306, A123307, A123308, A123309, A123310, A123311. %K A123312 nonn,more %O A123312 0,3 %A A123312 _Paul D. Hanna_, Sep 25 2006