A200054 Number of -5..5 arrays x(0..n-1) of n elements with zero sum and elements alternately strictly increasing and strictly decreasing

1, 10, 56, 324, 1948, 11962, 74338, 466548, 2947742, 18746754, 119701782, 767860824, 4938868628, 31876070432, 206122332340, 1336425077996, 8676994345132, 56457974059982, 367738443114696, 2399500033305708

Offset

1,2

Comments

Column 5 of A200057

Links

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

Example

Some solutions for n=6
.-2...-5....3...-4...-5....0...-4....5...-2....4....0....5...-4...-2...-2....0
.-3....4...-3...-1....4...-3....4...-4...-5...-3....3...-5....0...-3....2....5
..5...-3....4...-5...-1....4...-4....1....2....3...-4....0...-3....2....0....0
.-1....2...-5....4....5...-4....3...-5...-3....0...-1...-3....2....0....4....1
..5....0....3....2...-2....5...-4....4....5....1...-3....2....1....3...-3...-5
.-4....2...-2....4...-1...-2....5...-1....3...-5....5....1....4....0...-1...-1

Crossrefs

Sequence in context: A087076 A014483 A116971 * A034195 A351458 A067250

Adjacent sequences: A200051 A200052 A200053 * A200055 A200056 A200057

Keyword

nonn

Author

R. H. Hardin Nov 13 2011

Status

approved