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A305770
Number of nXn 0..1 arrays with every element unequal to 0, 1, 2, 3, 5 or 7 king-move adjacent elements, with upper left element zero.
0
1, 8, 81, 1481, 51586, 3492739, 453853629, 113299205109, 54481875961523
OFFSET
1,2
COMMENTS
Diagonal of A305776.
EXAMPLE
Some solutions for n=5
..0..1..1..1..0. .0..0..1..0..1. .0..1..0..0..0. .0..0..1..0..0
..1..1..0..0..1. .0..1..0..1..0. .0..0..0..1..0. .1..0..0..0..0
..0..0..0..1..1. .0..1..1..0..0. .0..0..1..0..0. .0..0..0..0..1
..0..0..1..0..0. .0..1..0..1..0. .0..1..1..0..0. .0..0..0..0..0
..0..0..0..0..0. .0..0..1..0..1. .1..1..1..1..1. .1..0..1..0..0
CROSSREFS
Cf. A305776.
Sequence in context: A138439 A193563 A026845 * A145921 A304655 A100399
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jun 10 2018
STATUS
approved