A186164 1/4 the number of nX5 0..3 arrays with every element equal to exactly one or two of its horizontal and vertical neighbors

7, 2175, 253341, 37402872, 5033988714, 704281652979, 96951738076992, 13435825601048421, 1856827788245959473, 256908205340960558187, 35528479510856892673200, 4914300705034627821533085

Offset

1,1

Comments

Column 5 of A186168

Links

R. H. Hardin, Table of n, a(n) for n = 1..21

Example

Some solutions for 4X5 with a(1,1)=0
..0..0..0..1..1....0..0..0..0..0....0..0..0..3..3....0..0..0..2..2
..0..2..0..1..2....0..2..1..1..1....0..2..0..1..3....0..2..0..2..1
..1..2..2..1..2....0..2..2..3..3....0..2..2..1..1....0..2..0..3..1
..1..1..0..0..2....3..3..3..0..0....0..3..3..0..0....0..2..0..3..3

Crossrefs

Sequence in context: A125538 A373035 A129732 * A203686 A248142 A216472

Adjacent sequences: A186161 A186162 A186163 * A186165 A186166 A186167

Keyword

nonn

Author

R. H. Hardin Feb 13 2011

Status

approved