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%I #4 Apr 20 2012 08:11:19
%S 48,238,814,2424,6888,19070,52124,142276,386732,1058996,2893626,
%T 7993242,22024912,61440284,170755404,480735696,1346455548,3821566724,
%U 10775254120,30797445968,87331368670,251116424714,715543269216,2068260652366
%N Number of -3..3 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, six or seven distinct values for every i,j,k<=n
%H R. H. Hardin, <a href="/A211740/b211740.txt">Table of n, a(n) for n = 1..44</a>
%e Some solutions for n=5
%e ..2....2....3....0....3....2....0...-1...-2...-3...-1...-2....1....3...-1....0
%e ..0....3....2...-2....0...-3...-3...-1....1...-3...-2....1...-3....1...-1...-1
%e ..2....1....3...-1....3....1....0....2....1....2...-1....2....1...-1....3...-3
%e ..1....0...-2....0....0....2...-3....3....1...-3...-2....3...-3...-1...-1...-2
%e ..3....1...-3...-1...-3...-3...-2....2...-2....1....3....0...-3...-3....3....0
%e ..2....0....2....2....2....2....1...-1....1....2...-2....1....1...-1....2...-1
%K nonn
%O 1,1
%A _R. H. Hardin_ Apr 20 2012