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 A231216 #6 Jul 23 2025 06:18:30 %S A231216 23,156,1793,20027,226764,2534951,28439115,318236849,3565691309, %T A231216 39935313475,447387885717,5011544754282,56140525034274, %U A231216 628886833447925,7044850137852253,78916780609087401,884031405098540067 %N A231216 Number of (n+1)X(5+1) 0..2 arrays with no element unequal to a strict majority of its horizontal and vertical neighbors, with values 0..2 introduced in row major order. %C A231216 Column 5 of A231219 %H A231216 R. H. Hardin, <a href="/A231216/b231216.txt">Table of n, a(n) for n = 1..210</a> %e A231216 Some solutions for n=4 %e A231216 ..0..0..0..0..0..1....0..1..1..1..1..0....0..1..1..2..2..2....0..0..0..1..1..1 %e A231216 ..1..1..1..0..0..1....0..1..1..1..1..0....0..1..1..2..2..2....1..1..0..1..1..1 %e A231216 ..1..1..1..0..0..1....0..0..1..1..1..0....0..1..1..2..2..2....1..1..0..2..2..1 %e A231216 ..1..1..0..0..0..1....0..0..1..1..0..0....0..1..1..2..2..2....1..1..0..2..2..1 %e A231216 ..0..0..0..0..0..1....0..0..1..1..0..0....0..0..0..0..0..0....0..0..0..2..2..1 %K A231216 nonn %O A231216 1,1 %A A231216 _R. H. Hardin_, Nov 05 2013