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 A224347 #7 Jul 23 2025 05:06:23 %S A224347 3,36,788,19608,495985,12340932,300892325,7202270426,169987960308, %T A224347 3972599259664,92292550974356 %N A224347 Number of n X n 0..2 arrays with diagonals and antidiagonals unimodal and rows nondecreasing. %C A224347 Diagonal of A224353 %e A224347 Some solutions for n=3 %e A224347 ..0..1..1....0..0..1....1..2..2....0..0..0....1..2..2....0..0..0....0..0..1 %e A224347 ..1..1..2....1..1..2....0..1..2....0..0..2....0..2..2....0..1..2....2..2..2 %e A224347 ..2..2..2....0..1..1....1..1..1....0..2..2....0..0..1....0..0..0....0..2..2 %K A224347 nonn %O A224347 1,1 %A A224347 _R. H. Hardin_ Apr 04 2013