A199525 Number of -3..3 arrays x(0..n-1) of n elements with zero sum and no two consecutive zero elements.

1, 6, 36, 212, 1324, 8342, 53302, 343710, 2232322, 14582218, 95702528, 630544704, 4168091856, 27630031358, 183604587444, 1222672695812, 8157398577024, 54515075729370, 364861668341252, 2445239266293460, 16407415704050100

Offset: 1

Author

R. H. Hardin Nov 07 2011

Keywords

• nonn

Comments

Column 3 of A199530

Examples

			Some solutions for n=5
..3...-2...-3...-1....0....1....3...-2....1....3...-2....0....1....2...-3....3
.-3....1....2....1....2....3....0....0...-3....3....0...-3...-3....1...-1...-2
..2....1...-3....0...-2...-1....1....2....0...-3...-1....1....2...-2....3....1
.-3....3....3....1...-2...-1...-3...-2...-1....0....3....2....1...-3...-2...-2
..1...-3....1...-1....2...-2...-1....2....3...-3....0....0...-1....2....3....0
		

Links

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