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%I #4 Apr 16 2012 06:42:53
%S 25,69,177,427,1009,2339,5381,12315,28147,64367,147473,338895,781407,
%T 1808731,4202661,9803439,22952115,53927029,127112163,300515927,
%U 712369279,1692743195,4030861381,9616634755,22980554099,54994897249,131772223081
%N Number of -2..2 arrays x(i) of n+1 elements i=1..n+1 with set{t,u,v in 0,1}((x[i+t]+x[j+u]+x[k+v])*(-1)^(t+u+v)) having one, two, three, four or five distinct values for every i,j,k<=n
%H R. H. Hardin, <a href="/A211572/b211572.txt">Table of n, a(n) for n = 1..35</a>
%F Empirical: a(n) = 8*a(n-1) -14*a(n-2) -46*a(n-3) +172*a(n-4) +6*a(n-5) -626*a(n-6) +470*a(n-7) +1009*a(n-8) -1253*a(n-9) -709*a(n-10) +1354*a(n-11) +140*a(n-12) -663*a(n-13) +23*a(n-14) +148*a(n-15) -6*a(n-16) -12*a(n-17)
%e Some solutions for n=5
%e .-2....1....2....1....0....2...-2...-2...-1...-2...-1...-1....1....2...-2....2
%e .-1....1....2....0....1...-2...-2...-2...-2...-2....1...-1....1....0...-2...-2
%e .-2....1....2...-2...-1....0...-2....1...-1....1...-1....1...-2....2....2....0
%e .-1....1...-2....0....0....2....2...-2...-2...-2...-1...-1...-2...-2...-2....0
%e ..0...-2...-2...-2....0...-2....0....1...-1...-2...-1...-1...-2....0...-2...-2
%e .-1...-2...-2....0....0....2....0...-2....0...-2...-1...-1...-2....2....2....2
%K nonn
%O 1,1
%A _R. H. Hardin_ Apr 16 2012
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