%I #4 Apr 16 2012 06:50:47
%S 17,61,185,505,1301,3279,8057,19877,48327,119027,289945,717461,
%T 1757523,4374935,10781761,26985609,66861615,168098793,418354859,
%U 1055489197,2636379211,6669352191,16707630313,42352772917,106355179479,270028712725
%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 one, three, four, five or six distinct values for every i,j,k<=n
%H R. H. Hardin, <a href="/A211579/b211579.txt">Table of n, a(n) for n = 1..55</a>
%F Empirical: a(n) = 7*a(n-1) +5*a(n-2) -135*a(n-3) +146*a(n-4) +1064*a(n-5) -1994*a(n-6) -4450*a(n-7) +11503*a(n-8) +10456*a(n-9) -38079*a(n-10) -12441*a(n-11) +78724*a(n-12) +1556*a(n-13) -103670*a(n-14) +15762*a(n-15) +85188*a(n-16) -20943*a(n-17) -40966*a(n-18) +11896*a(n-19) +10080*a(n-20) -3060*a(n-21) -936*a(n-22) +288*a(n-23)
%e Some solutions for n=5
%e ..0...-2....0....0...-1....1....1....2....0....0....2...-1....1....1....1....2
%e ..0...-1....0....1....0....0....0....0....0....0....0....0...-2....0....0....0
%e ..0...-2...-2....0...-1...-2...-1...-2....0....2....1....1....1....2....2...-2
%e ..0...-1....0...-2....0...-1....0...-1....2....0....0....2...-2....1....1....0
%e ..1....2....0....0....0....0....0...-2....0...-1...-1...-1...-1....0....2...-2
%e ..2....0....2...-1....1....1....1....0....2...-2....0...-2....0....2....1....0
%K nonn
%O 1,1
%A _R. H. Hardin_ Apr 16 2012
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