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 A233260 #7 Sep 24 2024 14:59:56 %S A233260 236,32896,10620928,3439984640,1159192379392,393427728465920, %T A233260 134179300927602688,45829217084770353152,15662712220567239393280, %U A233260 5353914504847465071509504,1830206096861520940880625664 %N A233260 Number of 5Xn 0..5 arrays with no element x(i,j) adjacent to itself or value 5-x(i,j) horizontally or antidiagonally, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order (unlabeled 6-colorings with no clashing color pairs). %C A233260 Row 5 of A233256 %H A233260 R. H. Hardin, <a href="/A233260/b233260.txt">Table of n, a(n) for n = 1..210</a> %F A233260 Empirical: a(n) = 512*a(n-1) -65536*a(n-2) +2490368*a(n-3) +17825792*a(n-4) -2818572288*a(n-5) +51539607552*a(n-6) -274877906944*a(n-7) for n>11 %e A233260 Some solutions for n=2 %e A233260 ..0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1 %e A233260 ..2..5....2..5....2..0....0..1....2..0....0..2....0..2....2..5....2..1....5..4 %e A233260 ..2..0....3..1....1..3....0..2....4..3....4..5....5..3....4..3....0..2....2..1 %e A233260 ..4..0....5..3....1..3....4..3....5..2....2..4....1..0....1..5....0..2....3..4 %e A233260 ..3..5....4..5....4..5....5..3....0..2....0..1....2..4....3..0....0..2....5..3 %K A233260 nonn %O A233260 1,1 %A A233260 _R. H. Hardin_, Dec 06 2013