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 A232312 #10 Jul 23 2025 07:17:45 %S A232312 52,853,14042,231454,3815483,62897985,1036869496,17092731689, %T A232312 281772661177,4645005493684,76572638191385,1262295368124753, %U A232312 20808863766803180,343032876614802177,5654876487122281889 %N A232312 Number of (n+1)X(4+1) 0..1 arrays with every element equal to some horizontal or antidiagonal neighbor, with top left element zero. %C A232312 Column 4 of A232316 %H A232312 R. H. Hardin, <a href="/A232312/b232312.txt">Table of n, a(n) for n = 1..210</a> %F A232312 Empirical: a(n) = 19*a(n-1) -44*a(n-2) +43*a(n-3) -19*a(n-4) +4*a(n-5) -2*a(n-6) for n>7 %e A232312 Some.solutions.for.n=3 %e A232312 ..0..0..0..1..1....0..0..1..1..1....0..0..0..1..1....0..0..1..0..1 %e A232312 ..1..1..1..0..1....0..0..1..1..0....0..0..1..1..1....0..1..0..1..1 %e A232312 ..0..0..0..1..1....0..0..0..0..0....0..0..1..1..0....1..1..1..0..0 %e A232312 ..0..0..1..1..1....1..1..0..0..0....0..0..1..0..0....0..0..0..0..0 %K A232312 nonn %O A232312 1,1 %A A232312 _R. H. Hardin_, Nov 22 2013