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 A231834 #6 Jul 23 2025 06:42:48 %S A231834 16,188,4508,111621,2836554,71178861,1792092360,45099279326, %T A231834 1134900171250,28560684486812,718739864735561,18087411635523189, %U A231834 455177754069590473,11454748470680974894,288263810554257272575 %N A231834 Number of nX3 0..3 arrays with no element less than a strict majority of its horizontal and antidiagonal neighbors. %C A231834 Column 3 of A231839 %H A231834 R. H. Hardin, <a href="/A231834/b231834.txt">Table of n, a(n) for n = 1..210</a> %F A231834 Empirical: a(n) = 16*a(n-1) +206*a(n-2) +762*a(n-3) -3181*a(n-4) -9838*a(n-5) +4473*a(n-6) +18193*a(n-7) +2848*a(n-8) -6404*a(n-9) -1848*a(n-10) for n>11 %e A231834 Some solutions for n=4 %e A231834 ..1..0..0....3..0..0....2..1..1....0..0..0....2..2..3....3..2..1....3..1..0 %e A231834 ..0..0..2....0..0..3....1..3..2....2..1..2....2..3..0....1..1..0....1..0..0 %e A231834 ..0..1..2....2..2..2....3..1..1....0..0..1....1..0..0....0..0..1....0..0..3 %e A231834 ..1..3..3....3..3..3....1..1..2....0..2..2....1..1..3....0..1..2....0..0..0 %K A231834 nonn %O A231834 1,1 %A A231834 _R. H. Hardin_, Nov 14 2013