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A306055
Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 4, 6 or 7 king-move adjacent elements, with upper left element zero.
1
4, 12, 27, 58, 189, 526, 1344, 3772, 10515, 28556, 78229, 215789, 592845, 1625872, 4467698, 12281228, 33730035, 92646767, 254564003, 699373287, 1921217868, 5278121739, 14500765607, 39837021249, 109441946346, 300667702619
OFFSET
1,1
COMMENTS
Column 3 of A306060.
LINKS
FORMULA
Empirical: a(n) = a(n-1) +2*a(n-2) +11*a(n-3) +3*a(n-4) -13*a(n-5) -46*a(n-6) -37*a(n-7) +8*a(n-8) +45*a(n-9) +39*a(n-10) +9*a(n-11) -a(n-12) -3*a(n-13) for n>14
EXAMPLE
Some solutions for n=5
..0..1..0. .0..1..0. .0..1..0. .0..1..1. .0..1..0. .0..1..0. .0..0..0
..1..0..0. .1..0..0. .0..0..1. .1..0..1. .0..1..0. .0..0..1. .0..0..0
..0..0..0. .1..1..0. .0..0..0. .1..1..1. .1..1..1. .0..0..0. .0..0..0
..0..1..0. .1..0..1. .0..0..0. .1..1..0. .1..1..1. .0..0..1. .0..0..0
..0..0..1. .0..1..1. .0..1..1. .1..1..0. .1..1..1. .0..0..1. .0..0..0
CROSSREFS
Cf. A306060.
Sequence in context: A188814 A104384 A013697 * A212522 A207408 A366998
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jun 18 2018
STATUS
approved