A211730 - OEIS

%I #4 Apr 20 2012 08:01:18

%S 48,238,714,1912,4946,12870,33484,89124,237726,649158,1771052,4937870,

%T 13708524,38836608,109246792,313321916,890240494,2577595902,

%U 7380219014,21526814774,62001807654,181885545056,526258853768,1550638116182

%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, three, four or six distinct values for every i,j,k<=n

%H R. H. Hardin, <a href="/A211730/b211730.txt">Table of n, a(n) for n = 1..53</a>

%e Some solutions for n=5

%e .-3...-3...-1...-3....3....2....1...-1....3....3...-1...-2....1....3....3....3

%e .-1...-2...-3....2...-1...-3....2...-2....3....1...-3...-2....3...-1....1....3

%e .-3....1...-1...-3....3....2...-1...-3....3...-1...-1...-1....1....3....3....1

%e .-1...-2....1....0....2...-1....0...-2...-3....1...-3...-2....3...-2....2...-1

%e .-1....1....3...-3....3....2....1...-3....3...-1...-1...-2....2...-1....0...-1

%e .-3....0....1....0...-1...-1....2....1....3...-3....1...-2....3....3....1...-1

%K nonn

%O 1,1

%A _R. H. Hardin_ Apr 20 2012