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A303726
Number of nX7 0..1 arrays with every element unequal to 0, 1, 2 or 3 king-move adjacent elements, with upper left element zero.
1
64, 719, 294, 406, 564, 894, 1476, 2252, 3461, 5631, 9362, 15569, 26111, 43960, 73883, 124371, 209956, 354631, 598917, 1012022, 1710721, 2891805, 4888812, 8266307, 13977941, 23636428, 39970625, 67595175, 114312998, 193321957, 326943993
OFFSET
1,1
COMMENTS
Column 7 of A303727.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) -a(n-4) -a(n-5) +a(n-7) -a(n-8) -a(n-9) +2*a(n-10) for n>18
EXAMPLE
Some solutions for n=5
..0..1..1..0..0..0..1. .0..1..1..0..0..0..1. .0..1..1..0..0..0..1
..1..1..1..0..0..0..0. .0..1..1..0..0..0..0. .1..1..1..0..0..0..0
..1..1..1..0..0..0..0. .0..1..1..0..0..0..0. .1..1..1..0..0..0..0
..1..1..1..0..0..0..0. .0..1..1..0..0..0..0. .1..1..1..0..0..0..1
..0..1..1..0..0..0..1. .0..1..1..0..0..0..0. .1..1..1..0..0..1..1
CROSSREFS
Cf. A303727.
Sequence in context: A320408 A223963 A372844 * A305229 A304774 A316517
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 29 2018
STATUS
approved