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 A277771 #4 Oct 29 2016 07:34:17 %S A277771 0,284,46289,8971150,1762881313,343944986355,67079817376928, %T A277771 13082674671680942,2551870774231153918,497725696443014836641, %U A277771 97078962056423037413261,18934823123149797267341357 %N A277771 Number of 6Xn 0..2 arrays with every element equal to some element at offset (-1,-1) (-1,0) (-1,1) (0,-1) (0,1) or (1,0) both plus 1 mod 3 and minus 1 mod 3, with new values introduced in order 0..2. %C A277771 Row 6 of A277767. %H A277771 R. H. Hardin, <a href="/A277771/b277771.txt">Table of n, a(n) for n = 1..63</a> %e A277771 Some solutions for n=3 %e A277771 ..0..1..2. .0..1..2. .0..1..2. .0..1..2. .0..1..2. .0..1..2. .0..1..2 %e A277771 ..2..2..0. .2..0..0. .2..1..0. .2..0..0. .2..1..0. .2..2..0. .2..2..0 %e A277771 ..1..1..2. .2..1..2. .0..0..2. .1..1..2. .1..0..1. .0..1..2. .2..1..2 %e A277771 ..0..1..0. .0..1..0. .2..1..2. .1..0..2. .1..2..2. .0..2..2. .0..2..1 %e A277771 ..2..0..1. .1..0..2. .0..2..0. .2..1..0. .0..1..2. .2..1..0. .2..1..0 %e A277771 ..1..2..2. .2..2..1. .0..1..0. .1..0..2. .2..2..0. .0..2..1. .0..1..2 %Y A277771 Cf. A277767. %K A277771 nonn %O A277771 1,2 %A A277771 _R. H. Hardin_, Oct 29 2016