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Number of nX3 0..2 arrays with no more than floor(nX3/2) elements unequal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..2 order
1

%I #5 Feb 25 2013 11:49:18

%S 1,5,9,112,426,4790,18007,208768,783389,9222742,34725955,412489970,

%T 1558983053,18631988604,70660866011,848302913944,3226795572945,

%U 38872008280152,148241838020273,1790674769103638,6843805534505557

%N Number of nX3 0..2 arrays with no more than floor(nX3/2) elements unequal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..2 order

%C Column 3 of A222587

%H R. H. Hardin, <a href="/A222583/b222583.txt">Table of n, a(n) for n = 1..202</a>

%e Some solutions for n=3

%e ..0..0..0....0..0..0....0..1..1....0..0..0....0..0..0....0..0..0....0..0..0

%e ..0..0..1....0..0..0....1..1..1....0..0..0....0..0..0....0..0..0....1..0..0

%e ..0..0..0....0..0..0....1..1..1....0..0..1....0..1..0....1..0..0....0..0..0

%K nonn

%O 1,2

%A _R. H. Hardin_ Feb 25 2013