A199702 Number of -6..6 arrays x(0..n-1) of n elements with zero sum and no two neighbors equal.

1, 12, 114, 1236, 13324, 147072, 1643204, 18527516, 210316392, 2400684208, 27527644696, 316844861020, 3658598730648, 42361908912360, 491666143730354, 5718341649577364, 66629811252553344, 777637357808739752

Offset: 1

Author

R. H. Hardin Nov 09 2011

Keywords

• nonn

Comments

Column 6 of A199704

Examples

			Some solutions for n=5
.-3....0...-4...-3....0....1...-3....3....4....1....6...-1....6...-4....4...-3
..0...-1....4....6...-2...-2....3....0....2...-1...-1...-5...-2....2...-6....6
..2....5....0...-6....2....0....5...-4....3....0....1...-2...-3....0...-1...-3
..3...-1...-4....3....5....6...-4....4...-6...-3...-2....3....4....3....1....5
.-2...-3....4....0...-5...-5...-1...-3...-3....3...-4....5...-5...-1....2...-5
		

Links

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