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%I #4 Apr 20 2012 08:10:20
%S 36,154,476,1312,3520,9400,25068,68180,185416,516528,1433876,4074308,
%T 11493872,33137744,94574204,275489652,792675160,2325832112,6730524532,
%U 19849806372,57673005088,170710336128,497407980332,1476146725844
%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 three, four, six or seven distinct values for every i,j,k<=n
%H R. H. Hardin, <a href="/A211739/b211739.txt">Table of n, a(n) for n = 1..50</a>
%F Empirical: a(n) = 4*a(n-1) +22*a(n-2) -99*a(n-3) -180*a(n-4) +970*a(n-5) +708*a(n-6) -4972*a(n-7) -1477*a(n-8) +14770*a(n-9) +1870*a(n-10) -26181*a(n-11) -2206*a(n-12) +26960*a(n-13) +2792*a(n-14) -14620*a(n-15) -1944*a(n-16) +3328*a(n-17) +320*a(n-18) -256*a(n-19)
%e Some solutions for n=5
%e .-1....3....3...-2....0....0...-3...-1...-3....1....2...-3....3....1...-1....3
%e .-3...-2....0....1....1...-2...-2...-3....0...-2...-1...-1....1....0...-2...-1
%e .-2...-3....3...-2....0....0...-1...-1...-3....1....0...-3....2....2....1...-2
%e .-3....2....0...-1....1...-2....2...-3...-2...-3...-1....2....0....1....0....1
%e .-2...-3....3....0...-2...-1....3....0....1....1...-3...-3....2....2....1...-2
%e ..0...-2....1...-1....1....2....0...-2....2...-3...-1...-1....1....1...-2...-3
%K nonn
%O 1,1
%A _R. H. Hardin_ Apr 20 2012
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