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 A203099 #7 Jul 22 2025 17:01:48 %S A203099 422,1705124,3790420430,7574530822364,15712898935252156, %T A203099 32766523337754473494,68145439667266350435686, %U A203099 141695919109060311625392330,294680177794961913094327501892 %N A203099 Number of nX6 0..3 arrays with every nonzero element less than or equal to some horizontal or vertical neighbor. %C A203099 Column 6 of A203101 %H A203099 R. H. Hardin, <a href="/A203099/b203099.txt">Table of n, a(n) for n = 1..210</a> %e A203099 Some solutions for n=5 %e A203099 ..1..1..0..1..1..0....3..3..3..3..0..1....1..2..3..1..0..1....2..3..3..2..2..2 %e A203099 ..3..0..2..1..1..0....2..0..2..1..1..1....3..3..3..3..2..1....2..2..1..1..1..2 %e A203099 ..3..1..3..1..0..2....3..2..1..1..0..1....1..2..2..0..0..2....2..3..0..1..2..2 %e A203099 ..0..1..3..0..2..2....3..0..2..1..1..0....1..1..2..2..0..2....0..3..3..3..2..1 %e A203099 ..0..2..3..3..1..0....2..0..3..3..2..1....3..3..2..1..2..2....2..2..1..2..1..1 %K A203099 nonn %O A203099 1,1 %A A203099 _R. H. Hardin_ Dec 29 2011