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 A302382 #4 Apr 06 2018 12:43:09 %S A302382 0,11,76,430,2886,19215,127535,847604,5631313,37416247,248600404, %T A302382 1651756796,10974620983,72917744789,484481101148,3218996316583, %U A302382 21387701319096,142104471542165,944172564092345,6273284870138765 %N A302382 Number of 3Xn 0..1 arrays with every element equal to 1, 2, 3 or 4 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. %C A302382 Row 3 of A302381. %H A302382 R. H. Hardin, <a href="/A302382/b302382.txt">Table of n, a(n) for n = 1..210</a> %F A302382 Empirical: a(n) = 4*a(n-1) +15*a(n-2) +14*a(n-3) +19*a(n-4) +8*a(n-5) +9*a(n-6) -9*a(n-7) +4*a(n-8) -5*a(n-9) +3*a(n-10) -3*a(n-11) -5*a(n-12) +a(n-13) -2*a(n-14) for n>15 %e A302382 Some solutions for n=5 %e A302382 ..0..1..1..0..1. .0..1..1..0..1. .0..0..0..1..0. .0..1..1..0..0 %e A302382 ..0..0..1..1..0. .0..0..1..1..0. .0..1..1..0..1. .1..0..0..1..0 %e A302382 ..0..0..1..0..0. .1..1..0..0..0. .0..0..0..1..1. .1..1..0..0..0 %Y A302382 Cf. A302381. %K A302382 nonn %O A302382 1,2 %A A302382 _R. H. Hardin_, Apr 06 2018