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%I #4 Apr 20 2012 08:00:38
%S 48,230,674,1788,4578,11854,30704,81648,217702,595826,1629412,4562734,
%T 12717112,36221068,102357152,295195208,842598926,2452480406,
%U 7051866394,20665527346,59743571278,175966514172,510748673328,1510003478102
%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, four or six distinct values for every i,j,k<=n
%H R. H. Hardin, <a href="/A211729/b211729.txt">Table of n, a(n) for n = 1..57</a>
%e Some solutions for n=5
%e ..0....0....1....0...-2...-2....1....2...-1...-3....0....2....1...-3....0....0
%e ..1...-1....0...-1...-2....3....2....1....0...-2....2...-1....3...-3...-3....1
%e ..2....0....1....0....3...-1....2...-2...-1...-1....2....2....1....0....0....2
%e .-1...-1....1....1...-2....3....3...-3...-1....0....2...-1....3...-3....1....2
%e ..0....2....0...-2....3...-1....3...-2....0...-2....2...-3....0...-3....2....2
%e ..3....1....1...-1...-2...-2....2...-3....3....0....0...-1....3...-3....1....3
%K nonn
%O 1,1
%A _R. H. Hardin_ Apr 20 2012
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