A193706 Number of arrays of -4..4 integers x(1..n) with every x(i) in a subsequence of length 1, 2, 3 or 4 with sum zero

1, 9, 69, 629, 3617, 23293, 150639, 974609, 6275983, 40514073, 261520865, 1687765963, 10892349861, 70298890683, 453700338187, 2928104677297, 18897520747299, 121961661224043, 787121398787181, 5079958229149695

Offset

1,2

Comments

Column 4 of A193710

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Example

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

Crossrefs

Sequence in context: A351810 A152273 A217452 * A275680 A167534 A110202

Adjacent sequences: A193703 A193704 A193705 * A193707 A193708 A193709

Keyword

nonn

Author

R. H. Hardin Aug 02 2011

Status

approved