A203050 Number of nX1 0..5 arrays with every nonzero element less than or equal to some horizontal or vertical neighbor

1, 6, 36, 161, 636, 2507, 10213, 42182, 173606, 710976, 2908797, 11911516, 48807427, 199987737, 819315100, 3356387171, 13749952752, 56330082115, 230771042950, 945410224602, 3873094298871, 15867039092263, 65003096433432

Offset

1,2

Comments

Column 1 of A203057

Links

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

Formula

Empirical: a(n) = 6*a(n-1) -15*a(n-2) +35*a(n-3) -35*a(n-4) +56*a(n-5) -28*a(n-6) +36*a(n-7) -9*a(n-8) +10*a(n-9) -a(n-10) +a(n-11)

Example

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

Crossrefs

Sequence in context: A371197 A225012 A228458 * A203332 A351783 A190065

Adjacent sequences: A203047 A203048 A203049 * A203051 A203052 A203053

Keyword

nonn

Author

R. H. Hardin Dec 28 2011

Status

approved