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 A201210 #7 Jul 22 2025 16:09:14 %S A201210 10,50,216,867,3318,12314,44858,161257,574237,2029778,7132780, %T A201210 24943546,86875164,301535122,1043529630,3602228998,12407419230, %U A201210 42653320657,146380696477,501599529832,1716499421419,5866845453921,20030578702565 %N A201210 Number of nX2 0..3 arrays with every row and column running average nondecreasing rightwards and downwards. %C A201210 Column 2 of A201216 %H A201210 R. H. Hardin, <a href="/A201210/b201210.txt">Table of n, a(n) for n = 1..180</a> %e A201210 Some solutions for n=7 %e A201210 ..0..0....0..3....0..1....0..0....0..1....0..0....0..0....0..0....0..0....0..1 %e A201210 ..0..1....0..3....0..1....1..2....0..1....1..2....0..2....0..2....0..0....0..1 %e A201210 ..2..2....1..3....0..1....1..1....0..1....1..2....1..1....0..1....0..2....1..1 %e A201210 ..2..2....3..3....0..1....1..3....0..2....1..3....1..2....2..2....3..3....2..3 %e A201210 ..2..3....3..3....3..3....2..3....1..3....1..3....1..2....3..3....2..3....3..3 %e A201210 ..2..3....2..3....2..2....1..3....2..2....1..3....1..2....2..2....1..3....3..3 %e A201210 ..2..3....2..3....2..2....1..3....1..3....1..3....2..3....2..3....2..3....3..3 %K A201210 nonn %O A201210 1,1 %A A201210 _R. H. Hardin_ Nov 28 2011