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 A276246 #4 Aug 25 2016 11:02:33 %S A276246 24,648,2837,26325,234431,2069454,18671229,167951009,1509288801, %T A276246 13609728840,122702955310,1106289221616,9981742768716,90071571350633, %U A276246 812807513045538,7336233541686365,66219228884217858,597727899610563029 %N A276246 Number of nX6 0..2 arrays with no element equal to any value at offset (-2,-1) (-1,1) or (0,-2) and new values introduced in order 0..2. %C A276246 Column 6 of A276248. %H A276246 R. H. Hardin, <a href="/A276246/b276246.txt">Table of n, a(n) for n = 1..210</a> %e A276246 Some solutions for n=4 %e A276246 ..0..1..1..0..0..2. .0..1..1..0..2..1. .0..1..1..2..0..1. .0..0..1..2..2..1 %e A276246 ..0..0..2..1..1..0. .0..0..2..1..0..0. .2..0..0..1..2..0. .1..2..0..0..2..2 %e A276246 ..1..1..0..0..2..2. .1..1..0..2..2..1. .2..2..0..0..1..1. .0..2..1..0..0..1 %e A276246 ..2..2..1..1..0..0. .2..1..1..0..2..1. .0..1..1..2..2..1. .0..0..1..1..2..0 %Y A276246 Cf. A276248. %K A276246 nonn %O A276246 1,1 %A A276246 _R. H. Hardin_, Aug 25 2016