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 A267931 #4 Jan 22 2016 10:08:45 %S A267931 222,49284,8459154,1376175262,205495778969,29057389299071, %T A267931 3909876972823819,505367954515309174,63080019343371599302, %U A267931 7640051013859497535548,901148367450672524043965 %N A267931 Number of nX4 0..3 arrays with every repeated value in every row and column greater than the previous repeated value. %C A267931 Column 4 of A267933. %H A267931 R. H. Hardin, <a href="/A267931/b267931.txt">Table of n, a(n) for n = 1..45</a> %e A267931 Some solutions for n=2 %e A267931 ..1..3..2..3....1..1..3..0....0..3..0..2....3..0..3..2....3..1..0..2 %e A267931 ..3..0..3..0....1..0..0..1....2..0..1..3....2..0..0..3....0..2..2..0 %Y A267931 Cf. A267933. %K A267931 nonn %O A267931 1,1 %A A267931 _R. H. Hardin_, Jan 22 2016