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 A201499 #9 Jul 22 2025 16:16:48 %S A201499 2,2,6,8,40,58,338,526,3334,5448,36168,61108,417920,723354,5054148, %T A201499 8908546,63260780,113093022,813360930,1470597342,10685501398, %U A201499 19499227828,142885700222,262754984020,1939096937920,3589093760726,26647143177214 %N A201499 Number of n X n 0..1 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 A201499 Diagonal of A201503 %H A201499 R. H. Hardin, <a href="/A201499/b201499.txt">Table of n, a(n) for n = 1..39</a> %e A201499 Some solutions for n=4 %e A201499 ..0..0..0..1....0..0..0..0....0..0..0..1....0..0..0..1....0..0..0..0 %e A201499 ..0..0..0..1....0..0..1..1....0..0..1..1....0..0..0..1....0..0..0..1 %e A201499 ..0..1..1..1....0..1..1..1....0..0..1..1....0..0..1..1....0..1..1..1 %e A201499 ..0..1..1..1....0..1..1..1....0..1..1..1....1..1..1..1....1..1..1..1 %K A201499 nonn %O A201499 1,1 %A A201499 _R. H. Hardin_ Dec 02 2011