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 A278633 #4 Nov 24 2016 10:22:46 %S A278633 1107,932205,541463431,309971214338,175644502146694,94782697883923436, %T A278633 47369705674953303984,21685396319356730003339, %U A278633 9098829152955190125398905,3522319073864419078316881080,1269570351401707348639148214535 %N A278633 Number of nX7 0..2 arrays with rows in nondecreasing lexicographic order and columns in nonincreasing lexicographic order, but with exactly two mistakes. %C A278633 Column 7 of A278634. %H A278633 R. H. Hardin, <a href="/A278633/b278633.txt">Table of n, a(n) for n = 1..19</a> %e A278633 Some solutions for n=1 %e A278633 ..1..2..2..0..0..1..0. .1..1..2..0..1..0..0. .1..2..2..1..2..2..2 %Y A278633 Cf. A278634. %K A278633 nonn %O A278633 1,1 %A A278633 _R. H. Hardin_, Nov 24 2016