A200448 Number of -2..2 arrays x(0..n+1) of n+2 elements with zero sum and nonzero first and second differences

10, 44, 144, 486, 1582, 5478, 18692, 64782, 223272, 776430, 2701660, 9439702, 33021250, 115801892, 406698282, 1430840312, 5040451088, 17779563894, 62784860258, 221948186878, 785340477204, 2781302241584, 9857972484436

Offset

1,1

Comments

Column 2 of A200454

Links

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

Example

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

Crossrefs

Sequence in context: A058310 A005720 A060326 * A124852 A220923 A220994

Adjacent sequences: A200445 A200446 A200447 * A200449 A200450 A200451

Keyword

nonn

Author

R. H. Hardin Nov 18 2011

Status

approved