A188117 - OEIS

A188117

Number of strictly increasing arrangements of n nonzero numbers in -(n+2)..(n+2) with sum zero

0, 4, 8, 31, 90, 308, 1032, 3528, 12124, 42262, 148518, 525869, 1874648, 6725266, 24260940, 87958188, 320349712, 1171609968, 4301272078, 15846418258, 58569008756, 217121189648, 807123533172, 3008133255026, 11238226082080

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OFFSET

1,2

COMMENTS

Column 4 of A188122

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..29

EXAMPLE

Some solutions for n=6

.-4...-7...-8...-6...-7...-8...-7...-8...-8...-5...-6...-5...-7...-8...-8...-3

.-3...-5...-6...-5...-3...-5...-5...-5...-6...-4...-4...-3...-6...-2...-7...-2

.-1...-1...-4...-3...-2...-3...-3...-3...-2...-1...-2...-2....1...-1....1...-1

..1....1....5....1...-1....3....4....2....2....1....1....1....3....1....2....1

..2....4....6....6....5....6....5....6....6....2....3....2....4....4....4....2

..5....8....7....7....8....7....6....8....8....7....8....7....5....6....8....3

CROSSREFS

Sequence in context: A374319 A149091 A149092 * A094502 A162459 A129195

Adjacent sequences: A188114 A188115 A188116 * A188118 A188119 A188120

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 21 2011

STATUS

approved