A201867 Number of zero-sum -2..2 arrays of n elements with first and second differences also in -2..2

1, 3, 5, 19, 45, 129, 345, 1031, 2969, 8803, 25791, 76285, 225047, 667807, 1984599, 5918017, 17672419, 52880691, 158447783, 475463579, 1428412619, 4296219727, 12934516047, 38978330199, 117561661847, 354857238103, 1071910795169

Offset

1,2

Comments

Column 2 of A201873

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Wolfdieter Lang, On Generating functions of Diagonals Sequences of Sheffer and Riordan Number Triangles, arXiv:1708.01421 [math.NT], August 2017.

Example

Some solutions for n=10
.-1....1...-1....2...-1...-1....1....2....2....0...-2...-2...-2....2...-2...-2
.-1....2...-2....2....0...-1....1....2....2...-1...-2...-2...-1....1....0...-2
..1....1...-1....2...-1...-1....0....2....1....0...-1....0....0...-1....0....0
..1....0....0....1...-1...-2...-1....0....1....2....0....2...-1...-2....1....0
..0...-1....1....0...-1...-1...-1...-1...-1....2....0....2...-1...-2....1....0
.-1...-1....0....0....0....0....0....0...-1....1....0....0...-1....0....1....0
..0....0....1...-2....0....1....1...-1....0....0....1...-1....1....1....1....0
..0...-1....1...-2....1....2....0...-1....0...-2....1....0....2....0...-1....1
..0....0....1...-2....2....2...-1...-1...-2...-2....1....0....1....1...-1....2
..1...-1....0...-1....1....1....0...-2...-2....0....2....1....2....0....0....1

Crossrefs

Sequence in context: A218373 A034511 A133603 * A148534 A148535 A148536

Adjacent sequences: A201864 A201865 A201866 * A201868 A201869 A201870

Keyword

nonn

Author

R. H. Hardin Dec 06 2011

Status

approved