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 A229367 #6 Jul 23 2025 05:40:55 %S A229367 22,184,1610,13937,122497,1067299,9346997,81633583,713982837, %T A229367 6240061504,54556988152,476904755485,4169201095109,36446367090562, %U A229367 318614423423484,2785298770230012,24348966185185668,212857075051476381 %N A229367 Number of nX3 0..2 arrays avoiding 11 horizontally, 22 vertically and 00 antidiagonally. %C A229367 Column 3 of A229372 %H A229367 R. H. Hardin, <a href="/A229367/b229367.txt">Table of n, a(n) for n = 1..210</a> %F A229367 Empirical: a(n) = 2*a(n-1) +61*a(n-2) +48*a(n-3) -586*a(n-4) -158*a(n-5) +2199*a(n-6) -1140*a(n-7) -1304*a(n-8) +440*a(n-9) +416*a(n-10) +64*a(n-11) %e A229367 Some solutions for n=4 %e A229367 ..0..2..0....1..0..1....0..1..2....0..2..2....1..0..2....0..0..1....1..0..0 %e A229367 ..0..1..2....2..2..0....1..0..1....0..1..0....2..0..1....2..0..1....1..2..1 %e A229367 ..1..2..1....0..1..0....1..2..1....0..2..2....1..2..1....1..0..1....2..1..0 %e A229367 ..2..0..2....0..2..1....0..0..2....0..0..1....1..0..2....2..2..1....0..2..1 %K A229367 nonn %O A229367 1,1 %A A229367 _R. H. Hardin_ Sep 21 2013