A200552 Number of -7..7 arrays x(0..n+1) of n+2 elements with zero sum and nonzero second differences.

154, 2134, 27806, 372150, 5012084, 68263780, 936121220, 12911643944, 178893425570, 2488110363432, 34717386812304, 485767803378730, 6813227225653584, 95761068651953630, 1348433104134460586

Offset: 1

Author

R. H. Hardin, Nov 19 2011

Keywords

• nonn

Comments

Column 7 of A200553.

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..83

Crossrefs

Cf. A200553.