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A317006
Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 3, 5, 6 or 8 king-move adjacent elements, with upper left element zero.
1
4, 23, 96, 400, 1704, 7313, 31328, 134118, 574442, 2460748, 10541124, 45155605, 193438738, 828663631, 3549885894, 15207276051, 65146190696, 279078852182, 1195542461428, 5121570860689, 21940242659146, 93989578468682
OFFSET
1,1
COMMENTS
Column 3 of A317011.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) -7*a(n-3) -27*a(n-4) -5*a(n-5) +14*a(n-6) +78*a(n-7) +49*a(n-8) -46*a(n-9) -81*a(n-10) +5*a(n-11) +55*a(n-12) -2*a(n-13) -39*a(n-14) -30*a(n-15) -8*a(n-16) for n>17
EXAMPLE
Some solutions for n=5
..0..0..0. .0..0..0. .0..0..0. .0..0..0. .0..0..0. .0..0..1. .0..1..0
..1..0..1. .0..0..0. .0..0..1. .0..0..0. .1..0..0. .1..0..0. .1..1..1
..0..0..0. .1..1..0. .1..0..0. .1..0..1. .1..1..0. .1..1..1. .1..0..1
..0..0..0. .1..0..0. .1..1..1. .0..0..0. .1..1..1. .1..1..0. .0..0..0
..0..1..0. .1..0..1. .1..0..1. .0..1..0. .1..1..0. .1..1..1. .0..0..0
CROSSREFS
Cf. A317011.
Sequence in context: A220647 A014585 A305588 * A227260 A316871 A197854
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jul 18 2018
STATUS
approved