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 A296829 #4 Dec 21 2017 12:41:33 %S A296829 5,14,43,132,402,1230,3755,11475,35054,107091,327180,999540,3053674, %T A296829 9329255,28501469,87074210,266018951,812707666,2482885810,7585415532, %U A296829 23174032657,70798497487,216295031546,660798311057,2018791013454 %N A296829 Number of nX3 0..1 arrays with each 1 adjacent to 0, 3 or 5 king-move neighboring 1s. %C A296829 Column 3 of A296834. %H A296829 R. H. Hardin, <a href="/A296829/b296829.txt">Table of n, a(n) for n = 1..210</a> %F A296829 Empirical: a(n) = 4*a(n-2) +20*a(n-3) +13*a(n-4) -27*a(n-5) -98*a(n-6) -115*a(n-7) -77*a(n-8) -13*a(n-9) -7*a(n-10) -15*a(n-11) -24*a(n-12) -4*a(n-13) +2*a(n-14) +4*a(n-15) %e A296829 Some solutions for n=7 %e A296829 ..0..0..0. .0..1..0. .0..1..1. .0..0..0. .0..1..0. .1..0..1. .0..1..0 %e A296829 ..0..1..0. .0..0..0. .0..1..1. .0..0..0. .0..0..0. .0..0..0. .0..0..0 %e A296829 ..0..0..0. .1..0..0. .0..0..0. .0..0..0. .0..0..0. .0..0..0. .1..0..1 %e A296829 ..0..0..0. .0..0..1. .1..1..0. .0..1..1. .1..1..0. .0..1..0. .0..0..0 %e A296829 ..0..0..1. .0..0..0. .1..1..0. .0..1..1. .1..1..0. .0..0..0. .0..0..0 %e A296829 ..1..0..0. .1..1..1. .0..0..0. .0..1..1. .1..1..0. .0..0..0. .0..1..0 %e A296829 ..0..0..1. .1..1..1. .1..0..1. .0..0..0. .0..0..0. .0..0..1. .0..0..0 %Y A296829 Cf. A296834. %K A296829 nonn %O A296829 1,1 %A A296829 _R. H. Hardin_, Dec 21 2017