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 A224369 #8 Aug 30 2018 06:07:18 %S A224369 22,218,1838,15540,132236,1126072,9588028,81634704,695055928, %T A224369 5917866680,50386093544,428998916880,3652596505952,31099055733376, %U A224369 264784589835472,2254437550085472,19194805371407680,163429034985577568 %N A224369 Number of n X 3 0..2 arrays with rows unimodal and antidiagonals nondecreasing. %C A224369 Column 3 of A224374. %H A224369 R. H. Hardin, <a href="/A224369/b224369.txt">Table of n, a(n) for n = 1..210</a> %F A224369 Empirical: a(n) = 10*a(n-1) - 16*a(n-2) + 30*a(n-3) - 14*a(n-4) + 12*a(n-5). %F A224369 Empirical g.f.: 2*x*(1 + x + x^2)*(11 - 12*x + 6*x^2) / (1 - 10*x + 16*x^2 - 30*x^3 + 14*x^4 - 12*x^5). - _Colin Barker_, Aug 30 2018 %e A224369 Some solutions for n=3: %e A224369 ..2..0..0....0..1..1....0..1..1....1..2..0....0..1..0....1..0..0....2..0..0 %e A224369 ..0..0..1....1..1..0....2..1..0....2..1..0....2..1..0....0..1..0....2..1..0 %e A224369 ..2..2..2....1..2..2....1..2..1....2..1..1....1..2..2....1..1..2....1..2..1 %Y A224369 Cf. A224374. %K A224369 nonn %O A224369 1,1 %A A224369 _R. H. Hardin_, Apr 05 2013