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 A231399 #7 Jul 23 2025 06:27:45 %S A231399 7,15,100,311,1706,7844,35696,184692,873979,4399412,22162876, %T A231399 110261498,564140421,2850848402,14542997263,74409026027,380043653506, %U A231399 1950717998012,10003505335070,51373261673575,264098740804503,1357567141208027 %N A231399 Number of (3+1)X(n+1) 0..2 arrays with no element unequal to a strict majority of its horizontal, diagonal and antidiagonal neighbors, with values 0..2 introduced in row major order. %C A231399 Row 3 of A231396 %H A231399 R. H. Hardin, <a href="/A231399/b231399.txt">Table of n, a(n) for n = 1..210</a> %H A231399 R. H. Hardin, <a href="/A231399/a231399.txt">Empirical recurrence of order 83</a> %F A231399 Empirical recurrence of order 83 (see link above) %e A231399 Some solutions for n=4 %e A231399 ..0..0..0..0..0....0..0..0..1..1....0..0..0..1..1....0..1..0..1..0 %e A231399 ..0..0..0..1..1....0..0..0..0..1....0..0..0..1..1....1..0..1..0..1 %e A231399 ..2..2..1..1..1....0..0..0..1..0....0..0..0..1..1....0..1..0..1..1 %e A231399 ..2..2..2..1..1....1..1..1..0..1....0..0..0..0..1....1..0..1..1..1 %K A231399 nonn %O A231399 1,1 %A A231399 _R. H. Hardin_, Nov 08 2013