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 A302634 #4 Apr 10 2018 19:31:32 %S A302634 21,185,83,304,1734,6460,30216,144266,642553,2942184,13568813, %T A302634 61798208,282661567,1295223226,5921237836,27085485076,123955468089, %U A302634 567032990681,2594025218639,11868355270058,54296922715587,248403802340878 %N A302634 Number of nX7 0..1 arrays with every element equal to 0, 1, 3 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. %C A302634 Column 7 of A302635. %H A302634 R. H. Hardin, <a href="/A302634/b302634.txt">Table of n, a(n) for n = 1..210</a> %e A302634 Some solutions for n=5 %e A302634 ..0..1..0..1..0..1..0. .0..1..1..0..0..1..0. .0..1..1..0..0..1..0 %e A302634 ..0..0..0..1..0..0..0. .0..1..0..1..0..1..0. .0..1..0..1..0..1..0 %e A302634 ..0..1..0..1..0..1..0. .0..1..0..1..0..1..0. .0..1..0..1..0..1..0 %e A302634 ..0..1..0..1..1..1..0. .0..0..0..1..1..1..0. .0..1..0..1..0..1..0 %e A302634 ..0..1..0..1..0..1..0. .0..1..0..1..0..1..0. .1..0..0..1..0..1..0 %Y A302634 Cf. A302635. %K A302634 nonn %O A302634 1,1 %A A302634 _R. H. Hardin_, Apr 10 2018