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 A304267 #4 May 09 2018 10:12:52 %S A304267 8,7,19,50,146,404,1074,2990,8316,22660,62314,172244,473150,1300260, %T A304267 3582364,9857308,27108012,74607826,205320218,564864078,1554286696, %U A304267 4277060278,11768341874,32381151240,89101629960,245170898378 %N A304267 Number of nX5 0..1 arrays with every element unequal to 0, 1, 5 or 8 king-move adjacent elements, with upper left element zero. %C A304267 Column 5 of A304270. %H A304267 R. H. Hardin, <a href="/A304267/b304267.txt">Table of n, a(n) for n = 1..210</a> %F A304267 Empirical: a(n) = a(n-1) +a(n-2) +10*a(n-3) +4*a(n-4) -2*a(n-5) -12*a(n-6) -5*a(n-7) -4*a(n-8) +4*a(n-9) for n>10 %e A304267 Some solutions for n=5 %e A304267 ..0..1..0..0..0. .0..0..0..0..0. .0..1..0..0..0. .0..1..0..0..0 %e A304267 ..0..0..0..0..0. .0..0..0..0..0. .0..0..0..0..1. .0..0..0..0..0 %e A304267 ..0..0..0..0..0. .1..0..0..1..0. .0..0..0..0..0. .0..0..0..0..1 %e A304267 ..0..0..1..0..0. .0..0..0..0..0. .1..0..0..0..0. .0..1..0..0..0 %e A304267 ..0..0..0..0..0. .0..0..0..0..0. .0..0..0..0..0. .0..0..0..0..0 %Y A304267 Cf. A304270. %K A304267 nonn %O A304267 1,1 %A A304267 _R. H. Hardin_, May 09 2018