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A304598
Number of n X n 0..1 arrays with every element unequal to 0, 1, 2, 5 or 6 king-move adjacent elements, with upper left element zero.
0
1, 4, 13, 73, 560, 6007, 75463, 1874284, 62934491, 2085910493, 94776909801, 7409071360844, 887762245576310
OFFSET
1,2
COMMENTS
Diagonal of A304604.
EXAMPLE
Some solutions for n=5
..0..0..0..1..0. .0..1..0..0..0. .0..0..0..1..0. .0..0..1..0..0
..0..0..0..0..0. .0..0..0..0..0. .0..0..0..0..0. .0..0..0..0..1
..1..1..0..0..1. .1..0..0..0..0. .0..0..0..0..1. .1..0..0..0..0
..1..1..0..0..0. .0..0..0..0..1. .0..0..0..0..0. .0..0..0..0..1
..0..0..0..0..0. .0..0..0..0..0. .0..1..0..1..0. .0..0..1..0..0
CROSSREFS
Cf. A304604.
Sequence in context: A374825 A121452 A249165 * A171756 A235385 A144055
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 15 2018
STATUS
approved