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 A266129 #4 Dec 21 2015 12:27:46 %S A266129 16,625,1959,44623,1285961,13689944,311260836,6688962679,100184677192, %T A266129 2265417750456,45483452144968,770435712461338,16815081540198455, %U A266129 333162387132057777,5991913305292420418,126615975061832318833 %N A266129 Number of nX6 integer arrays with each element equal to the number of horizontal, diagonal and antidiagonal neighbors exactly one smaller than itself. %C A266129 Column 6 of A266131. %H A266129 R. H. Hardin, <a href="/A266129/b266129.txt">Table of n, a(n) for n = 1..74</a> %e A266129 Some solutions for n=4 %e A266129 ..0..2..1..1..1..1....0..1..1..0..2..1....1..0..1..2..1..0....0..2..1..1..2..0 %e A266129 ..1..0..2..2..0..0....2..3..2..3..0..1....1..1..2..1..0..1....1..0..2..2..0..1 %e A266129 ..0..1..3..2..0..0....1..1..2..2..1..0....0..2..2..0..1..2....1..1..2..3..1..2 %e A266129 ..1..0..1..2..1..1....0..0..1..1..0..1....1..0..0..2..1..2....0..1..2..0..1..2 %Y A266129 Cf. A266131. %K A266129 nonn %O A266129 1,1 %A A266129 _R. H. Hardin_, Dec 21 2015