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 A300371 #4 Mar 04 2018 09:09:29 %S A300371 0,6,16,39,270,1592,12042,75739,490425,3084820,19634393,129519588, %T A300371 829432020,5341866361,34667291397,223006749453,1438573920539, %U A300371 9290258941352,59927615962595,386783857393798,2495707675837699 %N A300371 Number of nX7 0..1 arrays with every element equal to 2 or 3 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. %C A300371 Column 7 of A300372. %H A300371 R. H. Hardin, <a href="/A300371/b300371.txt">Table of n, a(n) for n = 1..210</a> %e A300371 Some solutions for n=5 %e A300371 ..0..0..0..0..0..0..0. .0..0..0..0..1..1..0. .0..0..0..0..1..1..0 %e A300371 ..0..1..1..1..1..1..0. .0..1..1..0..1..0..0. .0..1..1..0..1..0..0 %e A300371 ..1..0..0..1..0..1..0. .1..1..0..1..0..1..0. .0..1..0..0..1..1..1 %e A300371 ..1..0..0..0..0..1..0. .0..0..1..0..1..1..0. .0..0..1..1..0..0..1 %e A300371 ..1..1..1..1..1..0..0. .0..1..1..0..0..0..0. .0..1..1..0..0..1..1 %Y A300371 Cf. A300372. %K A300371 nonn %O A300371 1,2 %A A300371 _R. H. Hardin_, Mar 04 2018