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 A278625 #4 Nov 24 2016 08:45:11 %S A278625 266,31605,3438414,387542112,43853346948,4902306226424, %T A278625 540194658701142,58237100230743229,6049936223396297740, %U A278625 596291979361147397590,55176657492423943503531,4770167181501151268299031 %N A278625 Number of nX6 0..2 arrays with rows in nondecreasing lexicographic order and columns in nonincreasing lexicographic order, but with exactly one mistake. %C A278625 Column 6 of A278627. %H A278625 R. H. Hardin, <a href="/A278625/b278625.txt">Table of n, a(n) for n = 1..47</a> %e A278625 Some solutions for n=2 %e A278625 ..0..2..2..1..1..0. .1..0..2..1..0..0. .0..0..2..0..0..0. .2..0..0..2..1..0 %e A278625 ..1..2..1..0..0..1. .2..2..1..2..2..2. .2..1..1..2..2..2. .2..2..0..0..2..0 %Y A278625 Cf. A278627. %K A278625 nonn %O A278625 1,1 %A A278625 _R. H. Hardin_, Nov 24 2016