A199839 Number of -n..n arrays x(0..9) of 10 elements with zero sum and no two neighbors summing to zero

138, 88636, 3685550, 51077518, 389832124, 2044221894, 8281149188, 27785393300, 80752300406, 209581305608, 496408914210, 1090354976530, 2248071267000, 4391976524034, 8191437222152, 14673108432136, 25367684178562

Offset

1,1

Comments

Row 8 of A199832

Links

R. H. Hardin, Table of n, a(n) for n = 1..33

Formula

Empirical: a(n) = (124952/567)*n^9 - (35524/315)*n^8 + (50588/945)*n^7 - (2494/45)*n^6 + (13739/270)*n^5 - (1927/180)*n^4 - (41254/2835)*n^3 + (3319/420)*n^2 - (781/630)*n

Example

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

Crossrefs

Sequence in context: A163693 A089518 A223192 * A005447 A261703 A266003

Adjacent sequences: A199836 A199837 A199838 * A199840 A199841 A199842

Keyword

nonn

Author

R. H. Hardin Nov 11 2011

Status

approved