A212779 Half the number of 0..5 arrays of length n+2 with second differences nonzero.

99, 546, 3010, 16594, 91482, 504337, 2780392, 15328203, 84503842, 465866699, 2568306672, 14158984054, 78057979457, 430330886291, 2372398990909, 13078951921338, 72103800421506, 397505707375713, 2191434937861300

Offset

1,1

Comments

Column 5 of A212782.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +12*a(n-2) +12*a(n-3) -6*a(n-4) -18*a(n-5) -14*a(n-6) -11*a(n-7) -16*a(n-8) -11*a(n-9) -a(n-10).

Example

Some solutions for n=5
..3....0....4....3....1....1....3....1....4....1....4....3....4....0....3....3
..0....1....0....4....0....0....4....4....0....3....0....4....1....3....4....0
..2....5....3....1....1....1....4....3....5....4....5....1....2....3....4....0
..3....0....3....5....3....5....1....3....5....1....3....5....0....5....5....2
..3....1....5....2....3....5....3....1....0....1....3....5....4....4....5....0
..5....5....2....5....5....0....2....5....2....0....5....2....5....2....0....5
..2....1....0....2....5....2....5....2....0....2....0....0....4....2....3....0

Crossrefs

Cf. A212782.

Sequence in context: A157659 A273187 A322830 * A321636 A154359 A185499

Adjacent sequences: A212776 A212777 A212778 * A212780 A212781 A212782

Keyword

nonn

Author

R. H. Hardin, May 27 2012

Status

approved