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 A233729 #8 Jul 23 2025 08:10:31 %S A233729 2104,21432,233432,2723072,32240288,389230764,4696134192,57174669348, %T A233729 693181060760,8455863542400,102666251086924,1252787231370072, %U A233729 15219081421614496,185695021438104644,2256549296014445884 %N A233729 Number of (n+1)X(4+1) 0..3 arrays with every 2X2 subblock having the sum of the absolute values of the edge differences equal to 6 and no adjacent elements equal. %C A233729 Column 4 of A233733 %H A233729 R. H. Hardin, <a href="/A233729/b233729.txt">Table of n, a(n) for n = 1..210</a> %H A233729 R. H. Hardin, <a href="/A233729/a233729.txt">Empirical recurrence of order 84</a> %F A233729 Empirical recurrence of order 84 (see link above) %e A233729 Some solutions for n=2 %e A233729 ..0..1..3..1..2....2..0..2..0..2....2..0..1..2..0....2..0..3..1..3 %e A233729 ..2..3..2..0..3....3..2..1..2..1....3..2..0..3..2....0..1..2..0..2 %e A233729 ..0..1..0..1..2....2..0..2..0..2....1..3..1..2..0....2..0..3..2..1 %K A233729 nonn %O A233729 1,1 %A A233729 _R. H. Hardin_, Dec 15 2013