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 A280959 #4 Jan 11 2017 15:16:07 %S A280959 82,4850,63085,1121528,20029500,346289502,6052621154,105777297118, %T A280959 1846875100200,32253949107668,563278827019060,9836989060923111, %U A280959 171791531487108414,3000138481060751984,52393917402743354484 %N A280959 Number of nX6 0..2 arrays with no element equal to more than one of its horizontal, vertical and antidiagonal neighbors and with new values introduced in order 0 sequentially upwards. %C A280959 Column 6 of A280961. %H A280959 R. H. Hardin, <a href="/A280959/b280959.txt">Table of n, a(n) for n = 1..210</a> %e A280959 Some solutions for n=3 %e A280959 ..0..1..0..1..2..1. .0..1..0..1..0..2. .0..1..0..0..2..2. .0..1..0..1..1..0 %e A280959 ..2..0..1..0..2..1. .1..0..1..2..0..1. .2..1..2..1..0..1. .2..1..2..2..0..2 %e A280959 ..1..2..0..1..0..0. .2..2..0..2..1..2. .0..2..1..2..2..1. .0..0..1..1..2..1 %Y A280959 Cf. A280961. %K A280959 nonn %O A280959 1,1 %A A280959 _R. H. Hardin_, Jan 11 2017