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A281249
Number of nX4 0..2 arrays with no element equal to more than one of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.
1
1, 139, 8489, 197429, 3291920, 47427679, 622370435, 7668286112, 90290912746, 1027352752428, 11380794989335, 123393170675013, 1314462960605872, 13797631263124064, 143031796147222229, 1466895880313669174
OFFSET
1,2
COMMENTS
Column 4 of A281251.
LINKS
EXAMPLE
Some solutions for n=4
..0..1..2..1. .0..1..2..2. .0..0..0..1. .0..1..2..1. .0..0..1..0
..0..0..2..0. .0..1..0..1. .2..1..0..1. .1..0..1..2. .1..0..2..0
..2..1..2..0. .1..2..1..0. .0..2..2..0. .0..2..2..1. .2..1..2..2
..0..0..1..2. .0..0..1..0. .0..1..0..2. .2..1..0..2. .1..2..0..1
CROSSREFS
Cf. A281251.
Sequence in context: A223163 A158527 A201174 * A302089 A188452 A183491
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 18 2017
STATUS
approved