A193705 Number of arrays of -3..3 integers x(1..n) with every x(i) in a subsequence of length 1, 2, 3 or 4 with sum zero

1, 7, 43, 309, 1565, 8281, 43977, 233983, 1246261, 6642635, 35404681, 188678871, 1005542727, 5358879227, 28558908161, 152197318255, 811095694201, 4322522046735, 23035759794981, 122763158514755, 654234809106745

Offset

1,2

Comments

Column 3 of A193710

Links

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

Example

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

Crossrefs

Sequence in context: A199483 A331236 A042213 * A164775 A127999 A208595

Adjacent sequences: A193702 A193703 A193704 * A193706 A193707 A193708

Keyword

nonn

Author

R. H. Hardin Aug 02 2011

Status

approved