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A222840 Number of nX3 0..3 arrays with no more than floor(nX3/2) elements equal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..3 order.

%I A222840 #6 Jul 23 2025 03:08:18
%S A222840 2,105,4797,326408,15364848,1077545438,52487425596,3689615795056,
%T A222840 182579365380505,12856303224433084,643621625467714042,
%U A222840 45333053732314073754,2288743268254953421250,161184278096856509113288
%N A222840 Number of nX3 0..3 arrays with no more than floor(nX3/2) elements equal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..3 order.
%C A222840 Column 3 of A222842
%H A222840 R. H. Hardin, <a href="/A222840/b222840.txt">Table of n, a(n) for n = 1..64</a>
%e A222840 Some solutions for n=3
%e A222840 ..0..1..2....0..1..1....0..1..2....0..0..1....0..1..0....0..1..0....0..1..1
%e A222840 ..1..2..1....2..2..3....1..3..1....2..0..0....2..2..1....2..3..3....2..0..3
%K A222840 nonn
%O A222840 1,1
%A A222840 _R. H. Hardin_ Mar 06 2013