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 A224368 #8 Jul 23 2025 05:07:24 %S A224368 3,54,1838,77793,3607078,174854516,8684742989,437757725110, %T A224368 22283207886650,1142441203546438,58904154561219603, %U A224368 3051594326913582293,158760240705250821719,8291742411017787312243,434658935860309950718887 %N A224368 Number of n X n 0..2 arrays with rows unimodal and antidiagonals nondecreasing. %C A224368 Diagonal of A224374 %H A224368 R. H. Hardin, <a href="/A224368/b224368.txt">Table of n, a(n) for n = 1..24</a> %e A224368 Some solutions for n=3 %e A224368 ..0..0..0....2..0..0....0..0..0....1..2..0....2..1..1....1..0..0....1..1..0 %e A224368 ..0..1..1....2..1..0....1..0..0....2..2..1....2..1..0....1..0..0....2..0..0 %e A224368 ..1..1..0....1..1..2....2..2..1....2..1..0....1..2..0....0..2..0....1..1..2 %K A224368 nonn %O A224368 1,1 %A A224368 _R. H. Hardin_ Apr 05 2013