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 A300463 #4 Mar 06 2018 11:28:08 %S A300463 0,19,68,540,7456,78195,935121,10913850,127028268,1493618674, %T A300463 17461316528,204700167234,2397343348003,28083486453043, %U A300463 328982201480033,3853663395457966,45143074414088192,528811530208812741 %N A300463 Number of nX6 0..1 arrays with every element equal to 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. %C A300463 Column 6 of A300465. %H A300463 R. H. Hardin, <a href="/A300463/b300463.txt">Table of n, a(n) for n = 1..210</a> %e A300463 Some solutions for n=5 %e A300463 ..0..0..1..0..0..0. .0..0..1..1..0..0. .0..0..1..1..1..1. .0..0..1..1..0..0 %e A300463 ..0..1..1..0..0..1. .0..0..1..1..0..1. .0..1..1..0..1..1. .0..0..1..0..0..1 %e A300463 ..0..0..1..1..1..1. .0..0..1..0..1..1. .0..0..0..0..0..1. .0..0..0..0..1..1 %e A300463 ..0..1..1..0..1..0. .0..1..1..0..0..0. .0..0..1..0..1..0. .1..1..1..1..0..0 %e A300463 ..0..0..0..0..0..0. .1..1..0..0..0..0. .0..1..1..1..0..0. .1..1..1..0..0..0 %Y A300463 Cf. A300465. %K A300463 nonn %O A300463 1,2 %A A300463 _R. H. Hardin_, Mar 06 2018