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 A266158 #6 Aug 12 2016 06:55:34 %S A266158 1,0,0,0,0,2,0,0,0,8,0,0,0,16,48,0,0,0,40,1528,240,0,0,0,272,85976, %T A266158 71328,1968,0,0,0,5512,7699384,55409952,10109856,13824,0,0,0,149232, %U A266158 895747208,67579399344,118728695856,949116288,140160,0,0,0,3741272,121920870264 %N A266158 T(n,k)=Number of nXk arrays containing k copies of 0..n-1 with no element plus any horizontal, vertical or antidiagonal neighbor equal to n-1. %C A266158 Table starts %C A266158 .......1............0...............0................0...............0 %C A266158 .......0............0...............0................0...............0 %C A266158 .......2............0...............0................0...............0 %C A266158 .......8...........16..............40..............272............5512 %C A266158 ......48.........1528...........85976..........7699384.......895747208 %C A266158 .....240........71328........55409952......67579399344.108728430936384 %C A266158 ....1968.....10109856....118728695856.2180819465618592 %C A266158 ...13824....949116288.185137301064192 %C A266158 ..140160.197260755456 %C A266158 .1263360 %H A266158 R. H. Hardin, <a href="/A266158/b266158.txt">Table of n, a(n) for n = 1..60</a> %e A266158 Some solutions for n=4 k=4 %e A266158 ..3..1..1..0....0..2..2..3....1..1..1..0....0..1..1..3....0..1..3..2 %e A266158 ..3..1..0..2....0..2..3..1....1..0..0..2....0..1..3..2....1..3..2..0 %e A266158 ..1..0..2..2....2..3..1..0....0..2..2..3....1..3..2..0....1..3..2..0 %e A266158 ..0..2..3..3....3..1..0..1....2..3..3..3....3..2..2..0....1..3..2..0 %Y A266158 Column 1 is A173841. %K A266158 nonn,tabl %O A266158 1,6 %A A266158 _R. H. Hardin_, Dec 22 2015