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 A267908 #4 Jan 22 2016 07:58:03 %S A267908 11,726,47916,2331981,98614986,3774659262,134786758099,4574297266940, %T A267908 149403639631334,4738376096688749,146873341033699972, %U A267908 4471066919904073296,134165935575637438787,3980005021518381534082,116980704393934615092268 %N A267908 Number of nX4 0..2 arrays with every repeated value in every row unequal to the previous repeated value, and in every column equal to the previous repeated value, and new values introduced in row-major sequential order. %C A267908 Column 4 of A267911. %H A267908 R. H. Hardin, <a href="/A267908/b267908.txt">Table of n, a(n) for n = 1..210</a> %e A267908 Some solutions for n=3 %e A267908 ..0..1..1..0....0..0..1..1....0..1..2..1....0..1..2..1....0..1..2..1 %e A267908 ..1..1..2..2....1..0..1..2....1..2..0..0....2..0..0..1....1..0..2..0 %e A267908 ..2..1..1..2....1..1..2..2....1..0..1..1....1..2..0..1....2..0..2..2 %Y A267908 Cf. A267911. %K A267908 nonn %O A267908 1,1 %A A267908 _R. H. Hardin_, Jan 22 2016