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 A266184 #6 Aug 12 2016 06:53:59 %S A266184 6,22,88,296,1372,6128,29552,147570,755512,3945876,21025260,113229974, %T A266184 617874744,3397997370,18844357820,105109392654,589660050052, %U A266184 3322222401602,18796006629928,106695843736852,607569787629568 %N A266184 Number of 3Xn arrays containing n copies of 0..3-1 with no element plus any diagonal or antidiagonal neighbor equal to 3-1. %C A266184 Row 3 of A266183. %H A266184 R. H. Hardin, <a href="/A266184/b266184.txt">Table of n, a(n) for n = 1..73</a> %e A266184 Some solutions for n=4 %e A266184 ..1..2..0..2....2..0..2..1....2..0..2..1....1..2..0..2....0..2..0..2 %e A266184 ..2..0..1..1....0..2..0..1....0..1..0..2....1..0..1..0....2..0..2..0 %e A266184 ..1..2..0..0....1..0..2..1....0..1..2..1....0..2..1..2....1..1..1..1 %Y A266184 Cf. A266183. %K A266184 nonn %O A266184 1,1 %A A266184 _R. H. Hardin_, Dec 23 2015