A239172 Number of (n+1)X(2+1) 0..2 arrays with no element greater than all horizontal neighbors or equal to all vertical neighbors

26, 82, 676, 4338, 29380, 196698, 1321986, 8867938, 59528520, 399598612, 2681935810, 18001714474, 120831198520, 811019710990, 5443667518288, 36538530014326, 245249725777154, 1646142454877826, 11049078946194810

Offset

1,1

Comments

Column 2 of A239178

Links

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

Formula

Empirical: a(n) = 15*a(n-2) +149*a(n-3) +319*a(n-4) +372*a(n-5) -742*a(n-6) -1302*a(n-7) +296*a(n-8) +279*a(n-9) +1010*a(n-10) -921*a(n-11) +278*a(n-12) +747*a(n-13) -508*a(n-14) +361*a(n-15) -662*a(n-16) +626*a(n-17) -360*a(n-18) +80*a(n-19)

Example

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

Crossrefs

Sequence in context: A052241 A042332 A260199 * A291631 A325819 A138081

Adjacent sequences: A239169 A239170 A239171 * A239173 A239174 A239175

Keyword

nonn

Author

R. H. Hardin, Mar 11 2014

Status

approved