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 A301606 #4 Mar 24 2018 11:32:30 %S A301606 1,10,26,226,1297,8888,60841,421168,2940940,20639456,145157471, %T A301606 1021952648,7197614571,50704160874,357234289578,2517047832160, %U A301606 17735602594473,124970744650942,880592489506775,6205028171908948 %N A301606 Number of nX6 0..1 arrays with every element equal to 0, 2 or 3 horizontally or vertically adjacent elements, with upper left element zero. %C A301606 Column 6 of A301608. %H A301606 R. H. Hardin, <a href="/A301606/b301606.txt">Table of n, a(n) for n = 1..210</a> %e A301606 Some solutions for n=5 %e A301606 ..0..0..0..0..1..0. .0..0..0..1..1..1. .0..0..1..1..1..0. .0..0..0..0..0..1 %e A301606 ..0..1..0..0..0..1. .0..1..0..1..0..1. .0..0..1..0..1..1. .0..1..0..1..0..0 %e A301606 ..0..0..0..1..0..0. .0..0..0..1..1..1. .0..0..1..1..1..1. .0..0..0..0..0..0 %e A301606 ..0..1..0..0..1..0. .1..1..1..0..1..1. .1..1..1..0..0..0. .0..0..1..0..1..1 %e A301606 ..0..0..0..0..0..0. .1..1..1..1..1..1. .1..1..1..0..0..0. .0..0..0..0..1..1 %Y A301606 Cf. A301608. %K A301606 nonn %O A301606 1,2 %A A301606 _R. H. Hardin_, Mar 24 2018