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 A269080 #4 Feb 19 2016 08:48:55 %S A269080 64,659,10167,123976,1529241,18220241,210476400,2427784475, %T A269080 27272243911,306906072088,3392662878321,37516091561153, %U A269080 410121025237344,4478699111368451,48545701054002647,525277883650197736 %N A269080 Number of 6Xn binary arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two not more than once. %C A269080 Row 6 of A269075. %H A269080 R. H. Hardin, <a href="/A269080/b269080.txt">Table of n, a(n) for n = 1..210</a> %e A269080 Some solutions for n=4 %e A269080 ..0..0..0..1. .1..0..0..1. .0..0..0..1. .1..0..1..0. .1..0..0..0 %e A269080 ..1..0..0..0. .0..0..0..1. .0..0..0..0. .0..0..1..0. .1..0..0..0 %e A269080 ..0..1..0..1. .1..0..0..0. .0..0..0..1. .0..0..0..1. .1..0..0..0 %e A269080 ..0..0..0..1. .0..0..0..0. .0..0..0..0. .0..1..0..1. .1..0..0..0 %e A269080 ..0..1..0..0. .1..0..1..1. .0..0..0..0. .0..0..0..0. .0..0..0..1 %e A269080 ..0..0..0..1. .1..0..0..0. .1..0..0..1. .0..0..0..0. .1..1..0..1 %Y A269080 Cf. A269075. %K A269080 nonn %O A269080 1,1 %A A269080 _R. H. Hardin_, Feb 19 2016