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 A201444 #8 Jul 22 2025 16:15:13 %S A201444 4,2,52,112,4544,16334,1129682,5464208,458459214,2605975384, %T A201444 253569083138,1617730690396 %N A201444 Number of n X n 0..3 arrays with every row and column nondecreasing rightwards and downwards, and the number of instances of each value within one of each other. %C A201444 Diagonal of A201451 %e A201444 Some solutions for n=6 %e A201444 ..0..0..0..0..0..1....0..0..0..0..1..1....0..0..0..1..2..2....0..0..0..0..1..1 %e A201444 ..0..0..1..2..2..2....0..0..0..0..1..1....0..0..1..1..2..3....0..0..0..0..2..2 %e A201444 ..0..0..1..2..3..3....0..1..1..1..1..1....0..1..1..2..2..3....0..1..1..1..2..2 %e A201444 ..1..1..2..2..3..3....2..2..2..2..2..3....0..1..1..2..2..3....1..1..2..2..2..2 %e A201444 ..1..1..2..2..3..3....2..2..2..3..3..3....0..1..1..2..2..3....1..1..2..3..3..3 %e A201444 ..1..1..2..3..3..3....2..3..3..3..3..3....0..3..3..3..3..3....3..3..3..3..3..3 %K A201444 nonn %O A201444 1,1 %A A201444 _R. H. Hardin_ Dec 01 2011