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A305687
Number of nX3 0..1 arrays with every element unequal to 1, 2, 3, 4, 5 or 6 king-move adjacent elements, with upper left element zero.
1
1, 25, 152, 1151, 8415, 61796, 453553, 3329201, 24436772, 179369495, 1316598259, 9664023496, 70935343213, 520675774985, 3821836201340, 28052835663739, 205911909175803, 1511423474214692, 11094068951867649, 81432085718227557
OFFSET
1,2
COMMENTS
Column 3 of A305692.
LINKS
FORMULA
Empirical: a(n) = 6*a(n-1) +8*a(n-2) +12*a(n-3) +11*a(n-4) -a(n-5) +a(n-6) +a(n-7) -a(n-8)
EXAMPLE
Some solutions for n=5
..0..1..1. .0..1..1. .0..0..0. .0..1..1. .0..0..1. .0..0..1. .0..1..1
..0..0..1. .0..1..0. .1..1..1. .0..1..0. .0..1..0. .1..1..1. .1..0..0
..1..0..0. .1..1..0. .1..1..1. .0..1..1. .1..1..0. .0..0..0. .0..1..1
..0..1..1. .0..0..0. .0..0..1. .0..1..0. .1..0..1. .1..0..0. .0..0..0
..0..0..1. .1..1..0. .0..1..0. .0..0..0. .1..0..1. .0..1..0. .0..1..0
CROSSREFS
Cf. A305692.
Sequence in context: A042214 A215760 A362314 * A147059 A317067 A031211
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jun 08 2018
STATUS
approved