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%I #4 Apr 16 2012 07:06:20
%S 24,116,448,1472,4444,12774,35650,97884,266054,720836,1948936,5282998,
%T 14342514,39132978,107104716,294823440,814517876,2262919142,
%U 6309912984,17683751676,49727073362,140446174060,397854724286,1131186110662
%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 two, three, four, five, six or eight distinct values for every i,j,k<=n
%H R. H. Hardin, <a href="/A211594/b211594.txt">Table of n, a(n) for n = 1..51</a>
%e Some solutions for n=5
%e ..0...-1...-1....0....0...-1...-2...-1....1...-2....1....2....1....2....0...-1
%e ..1....0...-2....1...-1...-2....0....2....0...-1....0....0...-1....2...-1...-2
%e .-2....2...-1....0....1...-1...-2....0...-1....1....1...-1...-1....0...-1....0
%e ..1....0....0...-1....0....0...-2...-2...-1....0...-1....0...-2...-1...-1...-1
%e .-2...-2....1....1....1....2...-2....0...-1...-1....1....2...-2....0...-1....0
%e ..1....0...-1....2....2....1...-2...-2...-2...-2....0....2....0...-1...-2....2
%K nonn
%O 1,1
%A _R. H. Hardin_ Apr 16 2012