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 A278806 #6 May 25 2024 23:52:27 %S A278806 36,1254,69834,6275546,725674326,89730161098,10811999412826, %T A278806 1224101415304069,128795068372302728,12581278164317910030, %U A278806 1143931690129837256876,97156838914464540981998 %N A278806 Number of n X 7 0..2 arrays with rows in nondecreasing lexicographic order and columns in nonincreasing lexicographic order. %C A278806 Column 7 of A278807. %H A278806 R. H. Hardin, <a href="/A278806/b278806.txt">Table of n, a(n) for n = 1..20</a> %e A278806 Some solutions for n=3 %e A278806 ..1..1..1..1..0..0..0. .2..1..1..0..0..0..0. .2..2..1..1..1..1..1 %e A278806 ..2..1..0..0..1..1..1. .2..2..1..2..1..0..0. .2..2..2..1..1..0..0 %e A278806 ..2..1..2..0..1..1..0. .2..2..2..1..1..2..1. .2..2..2..2..2..2..1 %Y A278806 Cf. A278807. %K A278806 nonn %O A278806 1,1 %A A278806 _R. H. Hardin_, Nov 28 2016