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 A297542 #4 Dec 31 2017 15:02:24 %S A297542 1,105,905,10234,205888,3015179,45293985,726450667,11267743659, %T A297542 174940837668,2737325839679,42676467159309,665276067132323, %U A297542 10380615509680131,161909949029518946,2525266352244161021 %N A297542 Number of nX6 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 2 or 3 neighboring 1s. %C A297542 Column 6 of A297544. %H A297542 R. H. Hardin, <a href="/A297542/b297542.txt">Table of n, a(n) for n = 1..210</a> %e A297542 Some solutions for n=5 %e A297542 ..0..1..1..1..0..0. .1..1..1..0..0..0. .1..1..1..1..0..0. .0..0..0..1..0..0 %e A297542 ..0..0..1..0..1..0. .0..1..0..1..1..0. .0..1..0..0..1..1. .0..0..1..0..1..1 %e A297542 ..0..0..0..0..1..1. .0..0..1..1..0..0. .1..0..0..0..1..1. .0..1..0..0..1..1 %e A297542 ..0..0..1..0..0..1. .0..0..0..0..1..0. .0..1..0..0..0..1. .0..1..1..0..1..1 %e A297542 ..0..1..1..1..1..0. .0..0..0..1..1..1. .1..1..1..1..1..0. .0..1..1..0..1..1 %Y A297542 Cf. A297544. %K A297542 nonn %O A297542 1,2 %A A297542 _R. H. Hardin_, Dec 31 2017