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%I
%S 4,10,26,68,176,458,1193,3103,8069,20982,54556,141854,368847,959072,
%T 2493770,6484280,16860367,43840173,113992823,296403114,770704718,
%U 2003979505,5210729566,13548892363,35229708616,91603972925,238187830252
%N Number of 0..3 arrays x(0..n-1) of n elements with each no smaller than the sum of its two previous neighbors modulo 4
%C Column 3 of A207100
%H R. H. Hardin, <a href="/A207095/b207095.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) -a(n-2) +a(n-3) -3*a(n-4) +a(n-6) -2*a(n-9) +2*a(n-12) +a(n-13) -a(n-16)
%e Some solutions for n=5
%e ..0....2....2....0....2....0....1....2....0....1....2....0....1....0....1....3
%e ..2....3....2....0....3....1....1....3....1....2....2....2....1....0....2....3
%e ..3....1....3....0....2....3....2....3....2....3....2....3....3....3....3....2
%e ..2....3....1....1....3....2....3....3....3....2....3....2....2....3....2....3
%e ..3....2....2....1....1....3....2....2....1....2....3....1....2....3....3....3
%K nonn
%O 1,1
%A _R. H. Hardin_ Feb 15 2012
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