A199517 Number of nX2 0..3 arrays with values 0..3 introduced in row major order, the number of instances of each value within one of each other, and every element equal to two or fewer horizontal or vertical neighbors.

1, 1, 45, 105, 6300, 15400, 1030230, 2559433, 182663916, 457744440, 34150210658, 86068056429, 6629396556290, 16775738245132, 1323517639910370, 3359302469625303, 270024529787133744, 686970966254338640

Offset

1,3

Comments

Column 2 of A199523

Links

R. H. Hardin, Table of n, a(n) for n = 1..41

Example

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

Crossrefs

Sequence in context: A144486 A376892 A199351 * A180971 A043442 A044232

Adjacent sequences: A199514 A199515 A199516 * A199518 A199519 A199520

Keyword

nonn

Author

R. H. Hardin, Nov 07 2011

Status

approved