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A316687
Number of nXn 0..1 arrays with every element unequal to 0, 1, 2, 6, 7 or 8 king-move adjacent elements, with upper left element zero.
0
1, 4, 8, 23, 88, 2081, 61454, 2431114, 257262996, 52155197669, 17033276992389, 11335703888987492, 14840834772251861064, 35171617032782262638585
OFFSET
1,2
COMMENTS
Diagonal of A316693.
EXAMPLE
Some solutions for n=5
..0..1..1..1..1. .0..0..0..0..0. .0..0..0..0..0. .0..0..0..0..0
..1..0..1..1..1. .0..0..0..0..0. .0..0..0..0..0. .0..0..0..0..0
..1..1..1..1..1. .0..0..0..0..0. .0..0..0..0..0. .0..0..0..0..0
..1..1..1..0..1. .0..0..1..1..0. .0..1..1..0..0. .0..1..0..1..0
..1..1..1..1..0. .0..0..0..0..0. .0..0..0..0..0. .1..0..0..0..0
CROSSREFS
Cf. A316693.
Sequence in context: A026596 A181688 A243557 * A083504 A277291 A362212
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jul 10 2018
STATUS
approved