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A188227
Number of nondecreasing arrangements of n numbers in -(2n-2)..(2n-2) with sum zero and not more than two numbers equal
1
1, 3, 12, 81, 598, 4859, 41748, 374820, 3475284, 33053399, 320869264, 3167899567, 31721907390, 321494911644, 3292220700520, 34018798556265, 354312456839426, 3716173628641396, 39220841304052510, 416264662788000213
OFFSET
1,2
COMMENTS
Diagonal of A188236
LINKS
EXAMPLE
Some solutions for n=4
.-1...-3...-3...-3...-4...-5...-6...-5...-4...-5...-3...-3...-2...-6...-2...-4
.-1....0...-2...-1...-1...-2...-1....0....1...-1...-1...-3...-2...-4...-1...-4
..1....1....0....1...-1....1....2....2....1....2....2....3....2....4....0....2
..1....2....5....3....6....6....5....3....2....4....2....3....2....6....3....6
CROSSREFS
Sequence in context: A197445 A303033 A207322 * A357665 A224608 A023881
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 24 2011
STATUS
approved