A200159 Number of -2..2 arrays x(0..n-1) of n elements with nonzero sum and with zero through n-1 differences all nonzero.

4, 8, 34, 76, 276, 700, 2276, 5992, 18542, 50488, 151814, 420680, 1241580, 3481308, 10162686, 28707288, 83211126, 236138900, 681383716, 1939299184, 5579324890, 15908310224, 45678520824, 130391096068

Offset: 1

Author

R. H. Hardin Nov 13 2011

Keywords

• nonn

Comments

Column 2 of A200165

Examples

			Some solutions for n=5
..2...-2...-1...-2....2...-1....1...-2...-2....1....2....1...-1....2...-1...-2
.-1...-1...-2....1....1....1....2....2....1...-1...-2...-1....2....1....1....1
.-2....2...-1...-1....2....2...-2...-1....2....1....2....1...-1...-2...-2...-1
..1...-2....1...-2...-1...-1....2...-2...-1...-2...-1...-1....1....2...-1...-2
.-1....1....2...-1...-2....2...-2....2....2...-1....1....1....2....1...-2....2