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 A223844 #7 Jul 23 2025 04:35:04 %S A223844 4,256,64660,32464394,24291817048,23571122875874,27578655986218632, %T A223844 37359132548315097216 %N A223844 Number of n X n 0..3 arrays with rows and columns unimodal. %C A223844 Diagonal of A223850 %e A223844 Some solutions for n=3 %e A223844 ..1..0..0....0..0..0....0..3..0....0..0..3....3..1..0....2..2..0....2..2..1 %e A223844 ..0..2..1....2..1..0....0..3..1....0..0..3....3..3..0....2..2..3....0..1..1 %e A223844 ..0..3..1....1..2..3....0..1..3....0..1..0....1..1..0....3..3..1....0..0..3 %K A223844 nonn %O A223844 1,1 %A A223844 _R. H. Hardin_ Mar 27 2013