A203297 Number of arrays of 14 nondecreasing integers in -n..n with sum zero and equal numbers greater than zero and less than zero

8, 36, 280, 1844, 9880, 43958, 168314, 568933, 1734054, 4842044, 12545910, 30469542, 69935848, 152731858, 319150868, 641127127, 1243115122, 2334434336, 4258292458, 7564553798, 13115830616, 22239519138, 36942424868, 60209406935

Offset

1,1

Comments

Row 7 of A203291

Links

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

Formula

Empirical: a(n) = 3*a(n-1) -a(n-2) -3*a(n-3) +a(n-4) -a(n-5) +4*a(n-6) -3*a(n-7) +3*a(n-8) +3*a(n-9) -4*a(n-10) -2*a(n-11) -3*a(n-12) -2*a(n-13) +8*a(n-15) +7*a(n-17) -2*a(n-18) -a(n-19) -5*a(n-20) -13*a(n-21) +3*a(n-22) +a(n-23) +5*a(n-24) +6*a(n-25) +5*a(n-26) +a(n-27) +3*a(n-28) -13*a(n-29) -5*a(n-30) -a(n-31) -2*a(n-32) +7*a(n-33) +8*a(n-35) -2*a(n-37) -3*a(n-38) -2*a(n-39) -4*a(n-40) +3*a(n-41) +3*a(n-42) -3*a(n-43) +4*a(n-44) -a(n-45) +a(n-46) -3*a(n-47) -a(n-48) +3*a(n-49) -a(n-50)

Example

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

Crossrefs

Sequence in context: A032794 A000757 A126756 * A181072 A058823 A244301

Adjacent sequences: A203294 A203295 A203296 * A203298 A203299 A203300

Keyword

nonn

Author

R. H. Hardin Dec 31 2011

Status

approved