A274852 Number of n X n 0..2 arrays with no element equal to any value at offset (-1,0) (0,-1) or (-2,-2) and new values introduced in order 0..2.

1, 3, 19, 118, 1085, 14414, 289494, 8474549, 367622030, 23768683063, 2264991184042, 321683159101264, 67771416854833971, 21147805661160867290, 9831636745023577739551, 6777168866402222336954286

Offset

1,2

Comments

Diagonal of A274858.

Links

R. H. Hardin, Table of n, a(n) for n = 1..17

Example

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

Crossrefs

Cf. A274858.

Sequence in context: A290477 A321002 A221184 * A139176 A302443 A126809

Adjacent sequences: A274849 A274850 A274851 * A274853 A274854 A274855

Keyword

nonn

Author

R. H. Hardin, Jul 09 2016

Status

approved