A200425 Number of -3..3 arrays x(0..n+2) of n+3 elements with zero sum and no two or three adjacent elements summing to zero

92, 520, 2232, 9898, 50592, 270848, 1432402, 7469120, 38883992, 203526914, 1071337158, 5658347658, 29934599276, 158560687098, 841075030030, 4468272429398, 23771639720040, 126620792508358, 675163140324368

Offset

1,1

Comments

Column 3 of A200430

Links

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

Example

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

Crossrefs

Sequence in context: A233311 A233309 A205992 * A107343 A355622 A231300

Adjacent sequences: A200422 A200423 A200424 * A200426 A200427 A200428

Keyword

nonn

Author

R. H. Hardin Nov 17 2011

Status

approved