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 A202553 #8 Jul 22 2025 16:38:40 %S A202553 2,8,66,1526,103806,22360610,15635171834,36727396390100 %N A202553 Number of n X n 0,1 arrays with the row and column sums nondecreasing. %C A202553 Diagonal of A202560 %e A202553 Some solutions for n=4 %e A202553 ..0..0..0..1....1..1..0..0....0..0..1..1....0..0..0..0....0..0..0..1 %e A202553 ..0..1..1..0....0..0..1..1....0..1..1..1....0..1..0..0....0..0..0..1 %e A202553 ..0..0..1..1....0..1..0..1....1..1..0..1....1..0..1..1....0..1..1..1 %e A202553 ..1..1..0..1....1..0..1..0....1..0..1..1....0..1..1..1....0..1..1..1 %K A202553 nonn %O A202553 1,1 %A A202553 _R. H. Hardin_ Dec 21 2011