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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
1, 3, 19, 118, 1085, 14414, 289494, 8474549, 367622030, 23768683063, 2264991184042, 321683159101264, 67771416854833971, 21147805661160867290, 9831636745023577739551, 6777168866402222336954286
OFFSET
1,2
COMMENTS
Diagonal of A274858.
LINKS
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
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jul 09 2016
STATUS
approved