A183940 Number of strings of n numbers x(i) in -5..5 with sums of x(i) and of x(i)*x(i+1) both zero

1, 1, 11, 39, 497, 2343, 22881, 177535, 1682939, 14821961, 149400849, 1447662427, 14866001809, 149548074379, 1531694916059, 15535552043969, 159929685546853, 1644687110377919, 17107437074253385, 178041145616880947

Offset

1,3

Comments

Column 5 of A183944

Links

R. H. Hardin, Table of n, a(n) for n = 1..21

Example

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

Crossrefs

Sequence in context: A127867 A138050 A341232 * A335077 A077568 A122014

Adjacent sequences: A183937 A183938 A183939 * A183941 A183942 A183943

Keyword

nonn

Author

R. H. Hardin Jan 08 2011

Status

approved