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A199835 Number of -n..n arrays x(0..5) of 6 elements with zero sum and no two neighbors summing to zero 1
10, 426, 3556, 15708, 49302, 124982, 273728, 538968, 978690, 1667554, 2699004, 4187380, 6270030, 9109422, 12895256, 17846576, 24213882, 32281242, 42368404, 54832908, 70072198, 88525734, 110677104, 137056136, 168241010, 204860370 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 4 of A199832

LINKS

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

FORMULA

Empirical: a(n) = n*(2*n+1)*(2*n-1)*(66*n^2-35*n+19)/15.

Empirical: G.f.: 2*x*(5+183*x+575*x^2+281*x^3+12*x^4) / (x-1)^6 . - R. J. Mathar, Aug 01 2014

EXAMPLE

Some solutions for n=3

..0....2....3....2...-1...-3....0...-1....2...-1....1....0....0...-1....0...-2

.-1...-1....0....1...-1....2....2...-3....2....0....3....2...-1....3....3...-2

..2...-1....1...-3....3....3....0....1...-3....2...-2....1....2...-2...-1...-1

..1...-2...-3...-3...-2....1...-1....0....2....2....0...-2...-3....1....0....3

.-2....0...-2....2....0....0...-1....2...-1....0...-1...-2...-1...-2...-3....0

..0....2....1....1....1...-3....0....1...-2...-3...-1....1....3....1....1....2

CROSSREFS

Sequence in context: A085000 A248553 A126154 * A001327 A288325 A222665

Adjacent sequences:  A199832 A199833 A199834 * A199836 A199837 A199838

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 11 2011

STATUS

approved

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Last modified September 29 14:39 EDT 2020. Contains 337432 sequences. (Running on oeis4.)