A186165 1/4 the number of nX6 0..3 arrays with every element equal to exactly one or two of its horizontal and vertical neighbors

19, 14748, 4762206, 1899336597, 704281652979, 268995986029278, 101554003879403823, 38514280297010210802

Offset

1,1

Comments

Column 6 of A186168

Links

Table of n, a(n) for n=1..8.

Example

Some solutions for 4X6 with a(1,1)=0
..0..0..0..2..2..2....0..0..0..2..2..0....0..0..0..2..2..0....0..0..0..2..2..0
..0..2..0..0..0..2....0..2..0..0..2..0....0..2..0..0..0..0....0..2..0..0..3..0
..3..2..1..2..0..3....3..2..1..1..2..0....0..2..2..2..2..2....1..2..2..3..3..0
..3..1..1..2..0..3....3..0..0..0..2..0....0..0..0..0..1..1....1..0..0..3..2..2

Crossrefs

Sequence in context: A174306 A270069 A357252 * A198412 A110392 A107100

Adjacent sequences: A186162 A186163 A186164 * A186166 A186167 A186168

Keyword

nonn

Author

R. H. Hardin Feb 13 2011

Status

approved