A199843 Number of -4..4 arrays x(0..n-1) of n elements with zero sum and no element more than one greater than the previous

1, 5, 18, 68, 239, 845, 2958, 10349, 36111, 126121, 441161, 1546353, 5432430, 19130949, 67536934, 238991556, 847646318, 3012890719, 10730694626, 38289978058, 136865206035, 489995352710, 1756812943841, 6307268945198

Offset

1,2

Comments

Column 4 of A199847

Links

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

Example

Some solutions for n=6
..2....1....3....3....1....1....3....2....3...-1....3....4....0....2....2....3
..3....2....2....4...-1....2....2....3....0....0....1....3....0....2....0....4
..4....2....0...-1....0....2....2...-1....1....1....2....0....1....1....1...-1
.-2...-2....1....0....1....1....0...-1....2....1...-1...-2....2....2....1...-3
.-4...-2...-3...-2....1...-2...-3...-2...-2...-1...-1...-1...-1...-3...-1...-2
.-3...-1...-3...-4...-2...-4...-4...-1...-4....0...-4...-4...-2...-4...-3...-1

Crossrefs

Sequence in context: A158879 A322497 A279488 * A109438 A164051 A134764

Adjacent sequences: A199840 A199841 A199842 * A199844 A199845 A199846

Keyword

nonn

Author

R. H. Hardin Nov 11 2011

Status

approved