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 A264372 #4 Nov 12 2015 07:54:51 %S A264372 1,1,80,3778,1742881,2546661201,16353452350876,411980921235969243 %N A264372 Number of (n+1)X(n+1) arrays of permutations of 0..(n+1)^2-1 with each element having directed index change 2,-2 -1,0 -1,2 1,0 or 0,-1. %C A264372 Diagonal of A264379. %e A264372 Some solutions for n=4 %e A264372 ..5..2..3..4..7....1..2..5..6..9....1..2..5..8..9....1..6..5..8..9 %e A264372 ..0..1.10.11.12....0..7.10..3..4....0..7.10..3.12....0..7.10..3..4 %e A264372 .15..6.13.18..9...15.12.13..8.17...11..6..4.14.17....2.16.15.18.17 %e A264372 .16..8.20.23.14...20.11.18.23.22...16.21.20.13.24...20.11.12.13.14 %e A264372 .21.22.17.24.19...21.16.14.24.19...15.22.23.18.19...21.22.23.24.19 %Y A264372 Cf. A264379. %K A264372 nonn %O A264372 1,3 %A A264372 _R. H. Hardin_, Nov 12 2015