%I #5 Mar 31 2012 12:36:44
%S 6,69,633,7799,91425,983981,9526987,82847704,652848538,4712696751,
%T 31480011434,196280028176,1150650039753,6380377582098,33631853768986,
%U 169225758487160,815686475352515,3777731764480697,16854911299206527
%N Number of nX4 0..2 arrays with rows and columns lexicographically nondecreasing and every element equal to at least one horizontal or vertical neighbor
%C Column 4 of A201539
%H R. H. Hardin, <a href="/A201535/b201535.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) is a polynomial of degree 80 for n>43
%e Some solutions for n=5
%e ..0..0..0..1....0..0..0..1....0..0..2..2....0..0..1..2....0..0..2..2
%e ..0..0..2..1....0..0..0..1....0..2..2..2....1..1..1..2....0..1..0..0
%e ..0..1..2..2....0..1..2..2....1..1..1..2....1..2..0..0....0..1..1..1
%e ..1..1..1..0....2..1..2..0....1..2..0..0....2..2..2..2....2..0..0..2
%e ..2..2..0..0....2..1..2..0....1..2..0..0....2..2..2..2....2..0..2..2
%K nonn
%O 1,1
%A _R. H. Hardin_ Dec 02 2011
|