A200208 Number of -n..n arrays x(0..6) of 7 elements with zero sum and nonzero second and third differences

90, 3940, 37226, 187530, 667620, 1910006, 4664818, 10140128, 20184636, 37418930, 65462890, 109237270, 175066404, 271040286, 407440210, 596771596, 854269356, 1198528290, 1651314456, 2238353836, 2990103390, 3941357552, 5132247474

Offset

1,1

Comments

Row 4 of A200204

Links

R. H. Hardin, Table of n, a(n) for n = 1..50

Example

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

Crossrefs

Sequence in context: A013394 A013395 A203733 * A017806 A035740 A017753

Adjacent sequences: A200205 A200206 A200207 * A200209 A200210 A200211

Keyword

nonn

Author

R. H. Hardin Nov 14 2011

Status

approved