A201870 Number of zero-sum -5..5 arrays of n elements with first and second differences also in -5..5

1, 5, 27, 173, 977, 5963, 36569, 229949, 1451137, 9210249, 58617915, 374278491, 2396497371, 15387074629, 99039136267, 638882616201, 4129364962373, 26735915952717, 173368759816541, 1125743820087835, 7318831174181965

Offset

1,2

Comments

Column 5 of A201873

Links

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

Example

Some solutions for n=7
..4...-1...-5....4....4....3...-2....2....5....2....0....5....0...-4...-2...-2
..5...-1...-2....2....4....1...-1....3....3....2...-1....1...-2...-2...-1....1
..3....2...-1...-1....0....2....0....0....1...-1...-1....1....0....0....0....3
.-1....4....0...-1...-2....0...-1...-2...-1....1...-1....1....2....1...-2....4
.-4....1....1...-3...-3...-1...-1....0...-2....0...-1...-2....0....2...-1....0
.-2....0....3...-2...-1...-2....2....0...-3...-1....2...-3...-1....1....1...-2
.-5...-5....4....1...-2...-3....3...-3...-3...-3....2...-3....1....2....5...-4

Crossrefs

Sequence in context: A202248 A225344 A109963 * A091101 A185622 A225309

Adjacent sequences: A201867 A201868 A201869 * A201871 A201872 A201873

Keyword

nonn

Author

R. H. Hardin Dec 06 2011

Status

approved