A199197 Number of nX4 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 zero or two horizontal or vertical neighbors

1, 21, 447, 11734, 341015, 10692835, 351517665, 11945622271, 415824209261, 14744482818827, 530560208277339, 19323001059102859, 710881996757208605

Offset

1,2

Comments

Column 4 of A199201

Links

Table of n, a(n) for n=1..13.

Example

Some solutions for n=5
..0..1..0..1....0..1..0..1....0..1..0..2....0..1..0..2....0..1..0..2
..2..3..1..2....1..2..3..0....2..3..2..1....3..2..1..3....2..3..2..3
..3..2..0..3....0..3..2..2....0..1..3..0....2..0..2..1....0..1..1..0
..0..3..1..2....3..1..2..2....2..3..1..2....3..2..1..3....3..1..1..2
..3..1..2..0....1..3..0..3....3..0..3..1....0..3..0..1....2..3..0..3

Crossrefs

Sequence in context: A041842 A215152 A199252 * A219419 A157014 A076552

Adjacent sequences: A199194 A199195 A199196 * A199198 A199199 A199200

Keyword

nonn

Author

R. H. Hardin Nov 03 2011

Status

approved