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%I #4 Apr 16 2012 07:00:42
%S 17,61,213,705,2293,7235,22491,68737,207725,621607,1846229,5452449,
%T 16029207,46976949,137331695,400884837,1168925307,3406992747,
%U 9928127547,28937875373,84376984733,246182651755,718778819599,2100421491357
%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, three, four, five, six or seven distinct values for every i,j,k<=n
%H R. H. Hardin, <a href="/A211587/b211587.txt">Table of n, a(n) for n = 1..51</a>
%e Some solutions for n=5
%e ..2....2...-1...-2...-2...-1...-1....1....1...-2....0...-1....2...-2....0....2
%e ..0....0....0...-1....0....0....0...-2...-2...-1....0....2...-1....0...-2....0
%e ..2...-2....2....0...-2...-2...-2....0....1...-2....0...-1....0...-1....0...-1
%e ..0...-1...-1....2....1....0...-1....1....0....0....0...-2....1....2....1...-2
%e ..2....2....2...-1....0....2....0....0....0...-1....1....0...-2...-1....0....0
%e ..1...-1....0....0...-2....1....2...-1....2....2....2...-2....1....0....2....1
%K nonn
%O 1,1
%A _R. H. Hardin_ Apr 16 2012