A202248 Number of zero-sum -4..4 arrays of n elements with adjacent element differences also in -4..4.

1, 5, 27, 171, 1077, 6963, 45523, 300417, 1995897, 13332697, 89461271, 602525231, 4070925653, 27580062519, 187294750351, 1274550544383, 8689294370837, 59336253329567, 405779196651853, 2778627840692687, 19049684072515863

Offset

1,2

Comments

Column 4 of A202252.

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Example

Some solutions for n=7
..3....0....0...-4....2...-3....0...-1....2....2...-3...-3....4....2...-1....2
..3....0....2....0...-2...-4...-1....3...-2....3....0....1....1....2...-2....1
..2....2....0...-3....1....0....3....1...-2....0....0....2....0...-1....1....1
..1...-1...-1....1...-3....0....0....3...-1...-1....4...-2...-2....2....1...-3
.-3...-3...-1....3....0....4...-3...-1...-1....0....1....1...-1....0...-1...-3
.-3....0....0....3....1....1....0...-1....1...-3....1....1...-2...-1....2....0
.-3....2....0....0....1....2....1...-4....3...-1...-3....0....0...-4....0....2

Crossrefs

Cf. A202252.

Sequence in context: A138772 A258789 A082425 * A225344 A109963 A201870

Adjacent sequences: A202245 A202246 A202247 * A202249 A202250 A202251

Keyword

nonn

Author

R. H. Hardin Dec 14 2011

Status

approved