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%I #4 Apr 16 2012 07:08:50
%S 24,80,246,716,2046,5782,16184,45312,126250,353302,986696,2770910,
%T 7777304,21945496,61932032,175572572,497905408,1417135306,4034892052,
%U 11520180346,32901609502,94162093264,269546074004,772772054834
%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, six, seven or eight distinct values for every i,j,k<=n
%H R. H. Hardin, <a href="/A211597/b211597.txt">Table of n, a(n) for n = 1..33</a>
%e Some solutions for n=5
%e ..1....2....2....1...-1....0....1...-1....0....0....2...-1...-2....1...-2....2
%e ..1....1....0...-2...-2....2....2...-2....1....1...-1....1...-2...-1....1....1
%e ..2....1....2...-1....1....2....2...-2...-2....0....2...-1....2...-1....1....0
%e ..1....2....1...-2....1....2....1...-1....1...-1....1...-1....2....1....1....2
%e ..1....0....2....1...-2....0....2....2....2....0...-2....1....2....1...-2....0
%e ..1....1....1...-2....1....1....0...-1....2...-1....1...-1....2...-1....1....2
%K nonn
%O 1,1
%A _R. H. Hardin_ Apr 16 2012