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A305511
Number of nX3 0..1 arrays with every element unequal to 1, 2, 5, 6 or 8 king-move adjacent elements, with upper left element zero.
1
1, 2, 5, 6, 8, 19, 33, 60, 107, 204, 375, 677, 1253, 2329, 4252, 7824, 14454, 26591, 48908, 90088, 165947, 305495, 562342, 1035675, 1907146, 3511035, 6465055, 11904935, 21919763, 40360338, 74316988, 136840634, 251963379, 463940762
OFFSET
1,2
COMMENTS
Column 3 of A305516.
LINKS
FORMULA
Empirical: a(n) = a(n-2) +4*a(n-3) +3*a(n-4) -4*a(n-6) -5*a(n-7) -a(n-8) -3*a(n-9) -2*a(n-10) for n>13
EXAMPLE
Some solutions for n=5
..0..0..0. .0..0..0. .0..1..0. .0..1..0. .0..0..0. .0..0..0. .0..1..0
..0..1..0. .0..1..0. .0..0..0. .0..0..0. .1..0..1. .0..1..0. .0..0..0
..0..0..0. .1..0..1. .0..0..0. .0..1..0. .0..0..0. .0..0..0. .0..0..0
..0..1..0. .1..1..1. .0..1..0. .1..0..1. .0..0..0. .0..0..0. .1..0..1
..0..0..0. .1..0..1. .0..0..0. .1..1..1. .0..1..0. .0..1..0. .0..0..0
CROSSREFS
Cf. A305516.
Sequence in context: A326854 A097685 A136369 * A269472 A351830 A244272
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jun 03 2018
STATUS
approved