A198510 Number of 2n X 6 0..4 arrays with values 0..4 introduced in row major order and each element unequal to exactly two horizontal and vertical neighbors.

1626, 308854, 59007820, 13127875861, 3023133941944, 714429326523241, 171400320611391344, 41515521989152410680, 10116919781533608842706, 2474972835936834280715447

Offset

1,1

Comments

Column 3 of A198511.

Links

Table of n, a(n) for n=1..10.

Example

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

Crossrefs

Cf. A198511.

Sequence in context: A097225 A345968 A186846 * A241493 A328452 A202985

Adjacent sequences: A198507 A198508 A198509 * A198511 A198512 A198513

Keyword

nonn

Author

R. H. Hardin, Oct 25 2011

Status

approved