login
A304691
Number of n X n 0..1 arrays with every element unequal to 1, 2, 3, 5 or 6 king-move adjacent elements, with upper left element zero.
0
0, 7, 56, 918, 37050, 2753404, 389403912, 111681916203, 65358224695742
OFFSET
1,2
COMMENTS
Diagonal of A304697.
EXAMPLE
Some solutions for n=5
..0..1..0..0..1. .0..1..1..0..1. .0..1..1..0..0. .0..0..1..0..1
..0..0..0..0..0. .0..1..1..0..0. .1..0..1..1..0. .1..0..1..1..1
..0..0..0..0..0. .1..0..1..1..0. .0..1..1..1..1. .1..1..1..1..0
..1..1..0..1..1. .0..1..0..1..0. .1..0..1..1..1. .0..1..1..1..1
..1..0..0..1..0. .0..0..1..0..0. .0..1..1..1..0. .1..1..0..1..0
CROSSREFS
Cf. A304697.
Sequence in context: A099345 A245249 A110830 * A218428 A365102 A274721
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 17 2018
STATUS
approved