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A281658
Number of 6Xn 0..2 arrays with no element equal to more than one of its horizontal, diagonal or antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.
0
0, 20444, 982206, 32771472, 1205962480, 37763465272, 1154703692514, 34504258166264, 1006968332779830, 28949112532504572
OFFSET
1,2
COMMENTS
Row 6 of A281653.
EXAMPLE
Some solutions for n=2
..0..1. .0..1. .0..1. .0..1. .0..1. .0..1. .0..1. .0..1. .0..0. .0..0
..0..2. .1..2. .1..1. .1..1. .1..1. .0..1. .0..2. .2..1. .0..1. .0..1
..0..1. .0..0. .2..2. .0..2. .0..2. .1..0. .0..1. .2..2. .0..1. .2..1
..1..1. .2..2. .0..0. .2..1. .2..0. .2..0. .1..1. .1..0. .0..1. .2..0
..0..2. .0..1. .2..2. .2..1. .1..0. .1..0. .2..1. .0..1. .2..2. .1..1
..0..1. .0..0. .0..1. .2..1. .1..2. .1..1. .0..1. .0..2. .1..0. .2..2
CROSSREFS
Cf. A281653.
Sequence in context: A269279 A234552 A223466 * A234304 A242619 A224619
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 26 2017
STATUS
approved