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%I #4 Mar 03 2013 03:37:49
%S 6,666,88552,12956013,1928517786,289452236157,43727219083464,
%T 6642633038715993,1013931851324206903,155405622159690335817,
%U 23903771940011196629121,3688080815279058966399672
%N Number of nX4 0..3 arrays with exactly floor(nX4/2) elements equal to at least one horizontal, vertical or antidiagonal neighbor, with new values introduced in row major 0..3 order
%C Column 4 of A222722
%H R. H. Hardin, <a href="/A222720/b222720.txt">Table of n, a(n) for n = 1..21</a>
%e Some solutions for n=3
%e ..0..1..2..0....0..1..0..0....0..1..2..2....0..1..0..1....0..1..2..0
%e ..2..0..3..0....2..3..2..1....3..0..2..1....0..0..0..2....3..0..0..1
%e ..1..0..0..0....0..2..3..3....1..0..2..3....0..2..3..1....2..1..1..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 03 2013