A200032 Number of -2..2 arrays x(0..n-1) of n elements with sum zero and with zeroth through n-1st differences all nonzero

0, 4, 2, 28, 26, 168, 214, 1140, 1882, 7930, 15222, 56732, 122760, 416928, 975508, 3116724, 7715598, 23651892, 60875844, 181428684, 479853296, 1403488666, 3783362306, 10927395294

Offset

1,2

Comments

Column 2 of A200038

Links

Table of n, a(n) for n=1..24.

Example

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

Crossrefs

Sequence in context: A095896 A286798 A123670 * A121667 A368767 A291844

Adjacent sequences: A200029 A200030 A200031 * A200033 A200034 A200035

Keyword

nonn

Author

R. H. Hardin Nov 12 2011

Status

approved