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 A267722 #4 Jan 20 2016 06:42:21 %S A267722 1,5,58,1398,55896,3353880,281725200,31553227440,4543664711040, %T A267722 817859648350080 %N A267722 Number of nX5 arrays of permutations of 5 copies of 0..n-1 with every element equal to at least one horizontal neighbor and the top left element equal to 0. %C A267722 Column 5 of A267724. %e A267722 Some solutions for n=4 %e A267722 ..0..0..3..3..3....0..0..1..1..1....0..0..1..1..1....0..0..0..3..3 %e A267722 ..0..0..0..2..2....3..3..3..2..2....2..2..2..2..2....0..0..1..1..1 %e A267722 ..1..1..1..1..1....3..3..2..2..2....3..3..0..0..0....2..2..3..3..3 %e A267722 ..2..2..2..3..3....1..1..0..0..0....3..3..3..1..1....1..1..2..2..2 %Y A267722 Cf. A267724. %K A267722 nonn %O A267722 1,2 %A A267722 _R. H. Hardin_, Jan 20 2016