A199842 Number of -3..3 arrays x(0..n-1) of n elements with zero sum and no element more than one greater than the previous.

1, 4, 13, 42, 132, 428, 1393, 4561, 15032, 49889, 166542, 558744, 1883028, 6370957, 21628455, 73641852, 251385571, 860067894, 2948380732, 10124956970, 34823894885, 119940097035, 413612099138, 1427945022753, 4934850614704

Offset: 1

Author

R. H. Hardin, Nov 11 2011

Keywords

• nonn

Comments

Column 3 of A199847.

Examples

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

Links

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