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%I #4 Mar 03 2014 16:07:49
%S 4,16,86,284,1506,4636,24298,73300,381280,1144292,5923512,17767180,
%T 91688754,275195668,1417323260,4257556764,21898760846,65830136636,
%U 338306366754,1017543445164,5226264297018,15725498143268,80738182410936
%N Number of nX4 0..2 arrays with no element equal to the sum modulo 3 of elements to its left or elements above it
%C Column 4 of A238726
%H R. H. Hardin, <a href="/A238722/b238722.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 50*a(n-2) -1020*a(n-4) +11131*a(n-6) -71319*a(n-8) +275531*a(n-10) -629492*a(n-12) +789744*a(n-14) -456320*a(n-16) +76800*a(n-18)
%e Some solutions for n=5
%e ..2..1..2..1....1..2..2..1....2..1..2..1....2..1..1..2....2..1..1..2
%e ..1..2..1..0....2..1..1..2....1..2..1..0....1..0..0..0....1..0..0..0
%e ..2..1..2..0....2..1..2..1....1..2..2..0....1..2..2..0....2..0..0..0
%e ..1..2..1..2....1..0..0..0....2..1..1..0....2..1..1..0....1..0..2..1
%e ..2..1..1..2....2..0..0..0....2..1..1..2....1..0..2..1....2..0..1..1
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 03 2014
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