A183941 Number of strings of n numbers x(i) in -6..6 with sums of x(i) and of x(i)*x(i+1) both zero

1, 1, 13, 51, 761, 4411, 47675, 442337, 4838487, 50772785, 584627697, 6723246423, 79912390369, 950827647493, 11420632394717, 137246445111917, 1661603816786741

Offset

1,3

Comments

Column 6 of A183944

Links

Table of n, a(n) for n=1..17.

Example

Some solutions for n=4
..0....4....0...-6....3...-3....1....4....0....5...-1....2....1....0...-1...-1
.-2....3....4....0....0....0....2....0...-6....0...-2....4....2...-1...-6....0
..0...-6....0....0...-3....3....1...-4....0...-5....2...-4...-2....0....3....1
..2...-1...-4....6....0....0...-4....0....6....0....1...-2...-1....1....4....0

Crossrefs

Sequence in context: A146143 A108919 A002792 * A022673 A152742 A213837

Adjacent sequences: A183938 A183939 A183940 * A183942 A183943 A183944

Keyword

nonn

Author

R. H. Hardin Jan 08 2011

Status

approved