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 A231377 #8 Sep 28 2018 15:19:15 %S A231377 4,21,93,378,1519,6126,24747,99964,403743,1630662,6586087,26600572, %T A231377 107437031,433927396,1752589551,7078534592,28589495207,115470119764, %U A231377 466372299261,1883631211124,7607798625811,30727139997676,124103854340837 %N A231377 Number of n X 3 0..1 arrays with no element less than a strict majority of its horizontal and vertical neighbors. %H A231377 R. H. Hardin, <a href="/A231377/b231377.txt">Table of n, a(n) for n = 1..210</a> %F A231377 Empirical: a(n) = 6*a(n-1) - 11*a(n-2) + 16*a(n-3) - 14*a(n-4) - 3*a(n-5) + 8*a(n-6) - 9*a(n-7) - 2*a(n-8) + 6*a(n-9) + 2*a(n-10) for n>11. %F A231377 Empirical g.f.: x*(4 - 3*x + 11*x^2 - 13*x^3 - 6*x^4 - 12*x^5 - 15*x^6 + 3*x^7 + 13*x^8 + 8*x^9 + 2*x^10) / (1 - 6*x + 11*x^2 - 16*x^3 + 14*x^4 + 3*x^5 - 8*x^6 + 9*x^7 + 2*x^8 - 6*x^9 - 2*x^10). - _Colin Barker_, Sep 28 2018 %e A231377 Some solutions for n=3: %e A231377 ..0..0..0....1..0..0....0..0..0....0..0..1....1..1..0....0..1..0....0..1..1 %e A231377 ..1..0..1....0..0..0....0..0..1....0..0..0....1..1..0....0..0..0....0..0..1 %e A231377 ..1..0..0....0..0..1....0..0..1....0..0..0....0..0..0....0..1..0....0..0..0 %Y A231377 Column 3 of A231382. %K A231377 nonn %O A231377 1,1 %A A231377 _R. H. Hardin_, Nov 08 2013