A188231 Number of nondecreasing arrangements of n numbers in -(n+2)..(n+2) with sum zero and not more than two numbers equal.

1, 5, 17, 81, 374, 1818, 8964, 45225, 231596, 1202495, 6313385, 33473871, 178991409, 964308854, 5229780968, 28531772394, 156491164870, 862470267275, 4774186037351, 26533145487533, 148001670048543, 828332995017980

Offset: 1

Author

R. H. Hardin Mar 24 2011

Keywords

• nonn

Comments

Column 4 of A188236

Examples

			Some solutions for n=5
.-4...-6...-3...-6...-7...-7...-4...-4...-6...-7...-5...-3...-7...-7...-7...-4
.-4...-5...-2...-3...-4...-2...-2...-2...-2...-1...-5...-3...-6...-3...-5...-3
.-1....0...-1....1....2...-1...-1...-1....0....0...-4...-1....3...-1....3...-1
..4....4...-1....1....4....5....0....2....4....2....7....1....5....5....3....3
..5....7....7....7....5....5....7....5....4....6....7....6....5....6....6....5
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..28