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A305764
Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 3, 4 or 7 king-move adjacent elements, with upper left element zero.
1
4, 30, 141, 684, 3282, 15874, 76613, 370087, 1787161, 8631009, 41682223, 201299206, 972149367, 4694874104, 22673308188, 109497913757, 528806506293, 2553805037346, 12333282715847, 59562049771856, 287647486358008
OFFSET
1,1
COMMENTS
Column 3 of A305769.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) +9*a(n-2) -6*a(n-4) +12*a(n-5) -3*a(n-6) -27*a(n-7) +17*a(n-8) -4*a(n-9) -7*a(n-10) +a(n-11)
EXAMPLE
Some solutions for n=5
..0..1..1. .0..1..1. .0..0..1. .0..0..1. .0..1..0. .0..0..1. .0..1..1
..1..1..1. .1..0..0. .0..1..1. .0..0..0. .1..1..1. .1..1..0. .0..0..1
..1..1..1. .0..0..1. .1..1..1. .1..0..1. .1..0..0. .1..0..1. .0..1..0
..1..1..1. .1..1..0. .0..1..1. .1..1..0. .0..0..0. .1..1..1. .0..0..0
..0..0..1. .1..1..1. .0..0..0. .0..0..1. .1..1..1. .1..1..0. .1..1..0
CROSSREFS
Cf. A305769.
Sequence in context: A281950 A316178 A375260 * A317113 A123351 A305525
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jun 10 2018
STATUS
approved