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%I #7 Jul 19 2018 09:50:09
%S 24,60,136,278,564,1102,2160,4170,8084,15586,30160,58306,113060,
%T 219478,427124,832842,1627284,3186354,6249740,12283214,24175236,
%U 47665998,94090952,186015186,368095480,729323938,1446163736,2870526594,5701393800
%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 or five distinct values for every i,j,k<=n.
%H R. H. Hardin, <a href="/A211571/b211571.txt">Table of n, a(n) for n = 1..37</a>
%F Empirical: a(n) = 5*a(n-1) - a(n-2) - 31*a(n-3) + 39*a(n-4) + 56*a(n-5) - 116*a(n-6) - 14*a(n-7) + 115*a(n-8) - 34*a(n-9) - 30*a(n-10) + 12*a(n-11).
%F Empirical g.f.: 2*x*(12 - 30*x - 70*x^2 + 201*x^3 + 117*x^4 - 454*x^5 - 24*x^6 + 397*x^7 - 76*x^8 - 99*x^9 + 34*x^10) / ((1 - x)*(1 - 2*x)*(1 - x - x^2)*(1 - 2*x^2)*(1 - 3*x^2)*(1 - x - 2*x^2 + x^3)). - _Colin Barker_, Jul 19 2018
%e Some solutions for n=5;
%e .-2...-1...-1....0...-2....0....0....2....2...-2....1...-1...-1....1....0....2
%e .-1....1....1....1....0....1...-2...-2...-2...-2...-1...-1...-2....1...-2...-1
%e ..0....0...-1....0....2....0....0...-2...-2...-2....1...-1...-1...-1....2...-1
%e ..1...-1...-1...-2....0...-1...-2....2...-2....1...-1....1....0....1....2...-1
%e ..0....1...-1....0...-2...-2....0....2....2...-2....1...-1...-1....1....2....2
%e .-1...-1...-1....1....2...-1...-2....2....0....1....1....1....0...-1....2...-1
%K nonn
%O 1,1
%A _R. H. Hardin_, Apr 16 2012
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