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 A278804 #6 Sep 03 2022 21:09:27 %S A278804 21,336,5767,110455,2179956,41299256,725674326,11698232451, %T A278804 172994405326,2356249442222,29713542257399,348752692539813, %U A278804 3828597575581476,39486426123589674,384123325152744838,3537191225894230125 %N A278804 Number of n X 5 0..2 arrays with rows in nondecreasing lexicographic order and columns in nonincreasing lexicographic order. %C A278804 Column 5 of A278807. %H A278804 R. H. Hardin, <a href="/A278804/b278804.txt">Table of n, a(n) for n = 1..109</a> %e A278804 Some solutions for n=4 %e A278804 ..1..1..1..1..0. .1..1..0..0..0. .1..1..0..0..0. .1..1..0..0..0 %e A278804 ..2..1..1..0..0. .1..1..1..0..0. .1..1..1..1..0. .1..1..1..1..0 %e A278804 ..2..2..0..1..2. .1..1..2..2..2. .2..0..1..0..1. .1..1..2..1..2 %e A278804 ..2..2..1..1..2. .2..1..1..2..2. .2..0..1..0..2. .2..1..1..1..0 %Y A278804 Cf. A278807. %K A278804 nonn %O A278804 1,1 %A A278804 _R. H. Hardin_, Nov 28 2016