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 A224389 #6 Jul 23 2025 05:08:47 %S A224389 84,7056,319769,9331553,211856287,4364554008,90682660877, %T A224389 1970202629627,44404431681110,1020688669518185,23669944875525397, %U A224389 551060981056174321,12857376512847673306,300489121615902701612,7032615140846782176382 %N A224389 Number of nX6 0..3 arrays with diagonals and antidiagonals unimodal and rows nondecreasing. %C A224389 Column 6 of A224391 %H A224389 R. H. Hardin, <a href="/A224389/b224389.txt">Table of n, a(n) for n = 1..210</a> %e A224389 Some solutions for n=3 %e A224389 ..0..0..1..2..2..2....0..1..1..1..1..3....2..2..2..2..2..3....0..2..3..3..3..3 %e A224389 ..0..2..3..3..3..3....0..0..1..3..3..3....2..2..3..3..3..3....2..2..2..2..2..3 %e A224389 ..0..0..3..3..3..3....0..2..2..2..2..2....0..0..1..1..2..2....0..0..0..0..0..0 %K A224389 nonn %O A224389 1,1 %A A224389 _R. H. Hardin_ Apr 05 2013