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%I #9 Jun 14 2014 02:39:38
%S 3,53,1211,27768,618013,13312100,278398992,5675814840,113227696037,
%T 2217264763644,42732777814040,812306057415128,15256867582390896,
%U 283555814061437456,5221245121601899736,95350283688266563344
%N Number of side-n hexagonal 0..2 arrays with values nondecreasing E, SW and SE.
%C Column 2 of A216937.
%H R. H. Hardin, <a href="/A216931/b216931.txt">Table of n, a(n) for n = 1..43</a>
%e Some solutions for n=3:
%e ......0.0.0..........0.0.1..........0.0.0..........0.0.1..........0.0.0
%e .....0.0.0.1........0.1.1.1........0.0.0.0........0.0.1.1........0.1.1.2
%e ....0.0.0.1.2......0.1.1.2.2......0.0.0.0.1......0.1.1.1.2......1.1.1.2.2
%e .....1.1.1.2........2.2.2.2........0.0.0.2........1.1.2.2........1.1.2.2
%e ......2.2.2..........2.2.2..........0.0.2..........2.2.2..........1.2.2
%K nonn
%O 1,1
%A _R. H. Hardin_, Sep 20 2012