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%I #4 Mar 15 2013 05:33:25
%S 2,10,64,489,3599,27803,212771,1656545,12904694,101255205,796288843,
%T 6286246396,49736262634,394474774687,3134464364251,24950223830205,
%U 198897142545467,1587722400605459,12689418744067169,101527684281703007
%N Number of 2Xn 0..2 arrays with no more than floor(2Xn/2) elements equal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..2 order
%C Row 2 of A223126
%H R. H. Hardin, <a href="/A223127/b223127.txt">Table of n, a(n) for n = 1..29</a>
%e Some solutions for n=3
%e ..0..1..1....0..1..0....0..1..1....0..1..0....0..1..2....0..1..0....0..1..1
%e ..2..1..0....0..0..2....2..0..2....1..2..1....2..0..0....2..0..2....2..0..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 15 2013