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 A302376 #4 Apr 06 2018 12:38:11 %S A302376 1,15,76,475,2771,16451,97160,574671,3397622,20089993,118787443, %T A302376 702368950,4152971123,24555730380,145193342488,858500551625, %U A302376 5076149984859,30014306641852,177468870003729,1049339576968817 %N A302376 Number of nX3 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 A302376 Column 3 of A302381. %H A302376 R. H. Hardin, <a href="/A302376/b302376.txt">Table of n, a(n) for n = 1..210</a> %F A302376 Empirical: a(n) = 4*a(n-1) +13*a(n-2) -5*a(n-3) -28*a(n-4) -11*a(n-5) +11*a(n-6) +4*a(n-7) +6*a(n-8) +24*a(n-9) +16*a(n-10) -32*a(n-11) %e A302376 Some solutions for n=5 %e A302376 ..0..0..1. .0..0..1. .0..0..1. .0..0..0. .0..0..0. .0..0..1. .0..0..1 %e A302376 ..1..1..0. .0..1..1. .1..1..0. .1..0..1. .1..1..1. .1..1..1. .1..1..1 %e A302376 ..0..0..0. .0..0..1. .0..1..0. .1..1..0. .1..1..0. .0..0..0. .0..1..0 %e A302376 ..1..0..0. .1..1..1. .1..0..1. .1..1..0. .1..0..0. .0..0..1. .1..0..1 %e A302376 ..1..1..0. .0..0..1. .0..1..1. .1..0..0. .1..1..1. .1..1..0. .1..1..1 %Y A302376 Cf. A302381. %K A302376 nonn %O A302376 1,2 %A A302376 _R. H. Hardin_, Apr 06 2018