login
A317155
Number of nX3 0..1 arrays with every element unequal to 0, 1, 3, 4, 5, 7 or 8 king-move adjacent elements, with upper left element zero.
1
3, 9, 14, 29, 73, 165, 394, 1068, 3018, 8840, 27026, 84994, 270787, 872634, 2836018, 9247013, 30224317, 98998110, 324515834, 1064292227, 3492203429, 11460903801, 37616725965, 123478685661, 405342852398, 1330642249789, 4368286232516
OFFSET
1,1
COMMENTS
Column 3 of A317160.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) +a(n-2) +9*a(n-3) -24*a(n-4) -25*a(n-5) +9*a(n-6) -3*a(n-7) +49*a(n-8) +17*a(n-9) +122*a(n-10) +28*a(n-11) -244*a(n-12) -106*a(n-13) +175*a(n-14) +40*a(n-15) -48*a(n-16) -2*a(n-17) +4*a(n-18) for n>20
EXAMPLE
Some solutions for n=5
..0..0..1. .0..0..1. .0..1..0. .0..0..0. .0..0..0. .0..1..1. .0..0..0
..0..0..0. .0..0..0. .0..0..0. .0..0..0. .0..0..0. .1..1..1. .0..1..0
..0..0..0. .0..1..1. .0..0..0. .0..0..0. .0..0..0. .1..1..1. .0..0..0
..0..0..1. .0..0..0. .0..0..0. .0..0..0. .1..0..0. .1..1..1. .0..0..0
..0..0..0. .0..0..1. .1..0..0. .0..1..0. .0..0..0. .1..0..1. .0..1..0
CROSSREFS
Cf. A317160.
Sequence in context: A305342 A197274 A316234 * A316422 A100785 A317038
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jul 22 2018
STATUS
approved