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 A297511 #4 Dec 31 2017 07:32:45 %S A297511 1,876,11405,88808,3075264,66289769,978288822,19677228473, %T A297511 410226893539,7428573953424,139931054756836,2750243232989133, %U A297511 52290968094715743,990034495588191380,19031260437956001426,364274317770524751427 %N A297511 Number of 6Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1 or 2 neighboring 1s. %C A297511 Row 6 of A297506. %H A297511 R. H. Hardin, <a href="/A297511/b297511.txt">Table of n, a(n) for n = 1..210</a> %e A297511 Some solutions for n=4 %e A297511 ..0..0..1..1. .0..1..0..0. .0..1..1..0. .0..0..0..0. .1..1..0..0 %e A297511 ..0..0..0..0. .0..0..1..0. .0..0..0..1. .1..1..0..0. .0..0..0..0 %e A297511 ..0..0..1..1. .0..1..1..0. .0..0..0..1. .0..0..1..0. .0..0..1..1 %e A297511 ..1..0..0..1. .0..0..0..1. .0..0..1..0. .0..0..0..0. .0..1..0..0 %e A297511 ..0..1..0..0. .0..0..0..0. .0..0..0..0. .0..1..1..0. .1..0..0..0 %e A297511 ..1..0..0..0. .1..1..0..0. .0..1..1..0. .0..1..0..0. .0..0..0..0 %Y A297511 Cf. A297506. %K A297511 nonn %O A297511 1,2 %A A297511 _R. H. Hardin_, Dec 31 2017