A200033 Number of -3..3 arrays x(0..n-1) of n elements with sum zero and with zeroth through n-1st differences all nonzero

0, 6, 14, 84, 264, 1450, 5268, 25070, 102854, 460146, 1954930, 8681238, 37537698, 165783402, 725328338, 3201189116

Offset

1,2

Comments

Column 3 of A200038

Links

Table of n, a(n) for n=1..16.

Example

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

Crossrefs

Sequence in context: A139257 A056842 A182752 * A219376 A130263 A213681

Adjacent sequences: A200030 A200031 A200032 * A200034 A200035 A200036

Keyword

nonn

Author

R. H. Hardin Nov 12 2011

Status

approved