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A317261
Number of nX3 0..1 arrays with every element unequal to 0, 1, 3, 4, 6, 7 or 8 king-move adjacent elements, with upper left element zero.
1
3, 7, 10, 21, 46, 91, 186, 409, 892, 1931, 4236, 9363, 20792, 46525, 104832, 237487, 540898, 1238373, 2848246, 6577977, 15248530, 35464687, 82722630, 193446597, 453383480, 1064658303, 2504274032, 5899032191, 13912945708, 32848848465
OFFSET
1,1
COMMENTS
Column 3 of A317266.
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) -3*a(n-2) +a(n-3) -12*a(n-4) +11*a(n-5) -6*a(n-6) +20*a(n-7) -17*a(n-8) +20*a(n-9) +a(n-10) +7*a(n-11) -30*a(n-12) -11*a(n-13) -8*a(n-14) +8*a(n-15) +8*a(n-16)
EXAMPLE
Some solutions for n=5
..0..0..1. .0..1..1. .0..0..0. .0..0..1. .0..0..0. .0..0..1. .0..0..0
..0..1..1. .1..1..1. .0..0..0. .0..0..0. .0..1..0. .0..1..1. .1..0..0
..1..1..1. .1..1..1. .0..0..0. .0..0..0. .0..0..0. .0..0..0. .1..1..0
..1..1..1. .0..1..1. .1..0..0. .0..0..1. .0..0..0. .0..0..1. .1..1..1
..1..1..1. .0..0..1. .1..1..0. .0..1..1. .1..0..0. .0..1..1. .1..1..1
CROSSREFS
Cf. A317266.
Sequence in context: A279912 A305477 A316306 * A363643 A024464 A127277
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jul 25 2018
STATUS
approved