%I #4 Mar 31 2012 12:35:56

%S 1,19,109,541,4769,40483,327223,2590527,20896283,167580009,1349709835,

%T 11155226611,93502733191,786281486125

%N Number of strings of n+2 numbers x(i) in -4..4 with the sum of x(i) equal to zero and the sums of x(i)*x(i+1) and x(i)*x(i+2) equal to each other

%C Column 4 of A184061

%e Some solutions for n=6

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

%e ..4...-1....1...-1....0....4....0...-4....0....1....2....0....1...-3....2....2

%e .-4...-4....4....4....3...-2....1...-1....0....2...-3...-1...-4....3...-4....0

%e .-1....2...-4...-1....4....4....0...-1....2...-3...-2...-2....3....3...-1...-2

%e .-4....1....0....0...-2....1...-2...-1....0....3....1....1....4....0....4....0

%e .-1....2....1...-2....1...-4....1....4....2....1....0....4...-2...-3....0....0

%e ..3....1....4....1...-4...-4....1....1....2...-3....0...-2...-1....0...-2...-4

%e ..4....0...-3....1...-1....2...-4....3...-3...-1....3....1....2...-2....3....2

%K nonn

%O 1,2

%A _R. H. Hardin_ Jan 09 2011