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 A300464 #4 Mar 06 2018 11:28:48 %S A300464 0,41,212,2585,55663,935121,17675111,330639367,6123205255, %T A300464 114735094931,2136975985538,39899944005038,744635053156875, %U A300464 13895291324256516,259332066899793610,4839626748377777725,90318818165804970003 %N A300464 Number of nX7 0..1 arrays with every element equal to 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. %C A300464 Column 7 of A300465. %H A300464 R. H. Hardin, <a href="/A300464/b300464.txt">Table of n, a(n) for n = 1..210</a> %e A300464 Some solutions for n=5 %e A300464 ..0..0..1..1..1..0..0. .0..0..0..0..0..1..1. .0..0..1..1..1..0..0 %e A300464 ..0..0..1..1..1..0..0. .0..0..1..0..0..1..0. .0..1..1..1..1..0..0 %e A300464 ..0..1..0..0..1..0..0. .0..1..1..1..0..0..0. .0..0..0..0..1..1..1 %e A300464 ..1..1..0..0..1..0..1. .0..0..1..0..1..0..0. .0..0..1..0..0..1..1 %e A300464 ..1..1..1..1..1..1..1. .0..0..0..1..1..0..0. .0..1..1..0..0..1..1 %Y A300464 Cf. A300465. %K A300464 nonn %O A300464 1,2 %A A300464 _R. H. Hardin_, Mar 06 2018