A199642 Number of nX3 0..2 arrays with values 0..2 introduced in row major order and each element equal to one or two horizontal and vertical neighbors.

1, 13, 112, 1265, 12748, 134748, 1396083, 14584050, 151837464, 1582988477, 16494233432, 171904221068, 1791430664487, 18669394073270, 194560012081184, 2027588187779377, 21130256645906468, 220206564513115724

Offset

1,2

Comments

Column 3 of A199647

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n) = 7*a(n-1) +41*a(n-2) -44*a(n-3) -111*a(n-4) -140*a(n-5) +291*a(n-6) -225*a(n-7) +511*a(n-8) +2150*a(n-9) -3007*a(n-10) -6248*a(n-11) -624*a(n-12) +19900*a(n-13) -14308*a(n-14) +15248*a(n-15) -13312*a(n-16) -1648*a(n-17) +21440*a(n-18) -5632*a(n-19) -3968*a(n-20) +5632*a(n-21) -14336*a(n-22) -8192*a(n-23) for n>24

Example

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

Crossrefs

Sequence in context: A264451 A299687 A300319 * A087609 A302307 A293873

Adjacent sequences: A199639 A199640 A199641 * A199643 A199644 A199645

Keyword

nonn

Author

R. H. Hardin, Nov 08 2011

Status

approved