A200547 Number of -2..2 arrays x(0..n+1) of n+2 elements with zero sum and nonzero second differences

14, 76, 280, 1240, 4978, 21626, 91058, 393660, 1686980, 7309386, 31632968, 137600876, 599055566, 2615427970, 11433493630, 50075195034, 219589525108, 964264276780, 4238966033150, 18655002576606, 82175337524524

Offset

1,1

Comments

Column 2 of A200553

Links

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

Example

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

Crossrefs

Sequence in context: A200554 A152100 A173962 * A240045 A280396 A010821

Adjacent sequences: A200544 A200545 A200546 * A200548 A200549 A200550

Keyword

nonn

Author

R. H. Hardin Nov 19 2011

Status

approved