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 A275351 #4 Jul 24 2016 10:04:16 %S A275351 365,104976,235072,1530060,20917472,351504904,5814135340,101593710948, %T A275351 1804283175916,31575745629020,553989175825432,9795187879275832, %U A275351 173209703832176748,3054645736558927796,53918074086885218288 %N A275351 Number of nX7 0..2 arrays with no element equal to any value at offset (-2,-1) (-2,1) or (-1,-2) and new values introduced in order 0..2. %C A275351 Column 7 of A275352. %H A275351 R. H. Hardin, <a href="/A275351/b275351.txt">Table of n, a(n) for n = 1..40</a> %e A275351 Some solutions for n=2 %e A275351 ..0..0..0..0..0..0..1. .0..0..1..2..1..2..1. .0..1..2..1..2..2..1 %e A275351 ..2..1..2..1..1..1..1. .2..0..1..2..0..1..2. .2..0..1..0..1..2..0 %Y A275351 Cf. A275352. %K A275351 nonn %O A275351 1,1 %A A275351 _R. H. Hardin_, Jul 24 2016