login
Number of strings of n+2 numbers x(i) in -7..7 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
0

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

%S 1,33,245,2145,35451,496519

%N Number of strings of n+2 numbers x(i) in -7..7 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 7 of A184061

%e Some solutions for n=4

%e .-7...-2....5....0....7....0....7....1....4....3....4....4....3....3...-4...-1

%e ..5....5....0...-1...-2...-4...-2....0...-1...-2....4....6....0...-4....3...-1

%e .-3...-2...-4....2...-4....0....0....0...-4...-3...-4...-6....4...-1...-4....3

%e .-4...-3...-1....0...-1....0...-5....2...-1....3....0....2...-6....3...-2....2

%e ..3...-3...-4...-1...-4....4...-6....3...-3...-1...-4....0...-3...-1....4...-5

%e ..6....5....4....0....4....0....6...-6....5....0....0...-6....2....0....3....2

%K nonn

%O 1,2

%A _R. H. Hardin_ Jan 09 2011