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 A200894 #9 Jul 15 2014 08:23:40 %S A200894 6,30,1848,352339,218373106 %N A200894 Number of n X n 0..5 arrays with every row and column running average nondecreasing rightwards and downwards, and the number of instances of each value within one of each other. %C A200894 Diagonal of A200902. %e A200894 Some solutions for n=3: %e A200894 ..0..1..2....0..3..2....0..2..1....0..0..2....0..3..2....0..2..3....0..3..2 %e A200894 ..0..4..4....0..3..4....0..5..5....1..3..4....1..5..4....2..4..3....1..5..5 %e A200894 ..3..5..5....1..5..5....1..4..3....1..5..5....2..4..3....1..4..5....1..4..4 %K A200894 nonn %O A200894 1,1 %A A200894 _R. H. Hardin_, Nov 23 2011