A199708 Number of -n..n arrays x(0..5) of 6 elements with zero sum and no two neighbors equal.

32, 708, 4964, 20116, 59992, 147072, 314532, 608420, 1089752, 1836600, 2946204, 4537152, 6751384, 9756388, 13747296, 18948952, 25618064, 34045344, 44557532, 57519592, 73336788, 92456792, 115371796, 142620672, 174790996, 212521224

Offset: 1

Author

R. H. Hardin Nov 09 2011

Keywords

• nonn

Comments

Row 6 of A199704

Examples

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

Links

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

Formula

Empirical: a(n)=3*a(n-1)-2*a(n-2)-a(n-3)+2*a(n-5)-a(n-6)-a(n-7)+2*a(n-8)-a(n-10)-2*a(n-11)+3*a(n-12)-a(n-13)