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 A284164 #6 Apr 05 2020 22:36:07 %S A284164 33,1689,154108,16699997,1852406216,213897742464,25064817057781, %T A284164 2981736353245523,357844048109256955,43278292532056389680, %U A284164 5263990195553603263431,643350359729498071977340 %N A284164 Number of n X 7 0..1 arrays with the number of 1's horizontally or vertically adjacent to some 0 equal to the number of 0's adjacent to some 1, with top left element zero. %C A284164 Column 7 of A284165. %H A284164 R. H. Hardin, <a href="/A284164/b284164.txt">Table of n, a(n) for n = 1..19</a> %e A284164 Some solutions for n=3 %e A284164 ..0..1..1..1..0..1..0. .0..1..0..0..1..1..1. .0..0..0..0..0..1..1 %e A284164 ..0..1..1..0..0..1..1. .1..1..1..0..1..1..0. .0..0..0..1..1..0..0 %e A284164 ..0..1..0..1..0..0..1. .0..0..1..0..0..1..0. .1..1..1..0..1..1..0 %Y A284164 Cf. A284165. %K A284164 nonn %O A284164 1,1 %A A284164 _R. H. Hardin_, Mar 21 2017