A246897 Number of length 5+4 0..n arrays with some pair in every consecutive five terms totalling exactly n

416, 16621, 173056, 1216081, 4971120, 17677453, 47799488, 120392449, 259777600, 536775181, 1005318336, 1828277521, 3107102096, 5168689261, 8183025280, 12745702273, 19117702368, 28308317869, 40691100800, 57882676561, 80386887856

Offset

1,1

Comments

Row 5 of A246892

Links

R. H. Hardin, Table of n, a(n) for n = 1..65

Formula

Empirical: a(n) = 2*a(n-1) +5*a(n-2) -12*a(n-3) -9*a(n-4) +30*a(n-5) +5*a(n-6) -40*a(n-7) +5*a(n-8) +30*a(n-9) -9*a(n-10) -12*a(n-11) +5*a(n-12) +2*a(n-13) -a(n-14)

Example

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

Crossrefs

Sequence in context: A224602 A249006 A249471 * A223422 A239191 A324613

Adjacent sequences: A246894 A246895 A246896 * A246898 A246899 A246900

Keyword

nonn

Author

R. H. Hardin, Sep 06 2014

Status

approved