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%I #7 Jun 22 2022 11:42:14
%S 2,78,814,9667,110674,1282814,14823037,171459557,1982720806,
%T 22929915669,265174801858,3066662593835,35464903052433,
%U 410139828611289,4743130059530921,54852719114258196,634353415473617224
%N Half the number of n X 3 0..3 arrays with each element equal to either the maximum or the minimum of its horizontal and vertical neighbors.
%C Column 3 of A183584.
%H R. H. Hardin, <a href="/A183578/b183578.txt">Table of n, a(n) for n = 1..200</a>
%e Some solutions with a(1,1)<=1 for 5 X 3
%e ..0..0..0....1..0..0....0..0..2....1..0..0....0..0..3....0..1..1....1..0..1
%e ..0..3..3....1..1..0....0..2..2....1..1..1....0..0..3....0..0..0....1..0..1
%e ..1..0..0....0..0..2....2..1..2....3..0..0....3..3..3....2..2..0....1..0..0
%e ..1..1..1....0..0..2....2..1..1....3..0..0....2..2..3....0..0..0....0..1..0
%e ..0..0..1....0..1..1....1..1..1....3..0..0....2..2..2....0..1..1....0..1..0
%Y Cf. A183584.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 05 2011
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