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A317371
Number of nX3 0..1 arrays with every element unequal to 1, 2, 3, 4, 6, 7 or 8 king-move adjacent elements, with upper left element zero.
1
1, 23, 91, 529, 2870, 15382, 83982, 455180, 2470224, 13414200, 72799534, 395190412, 2145176236, 11644256732, 63207599222, 343101702044, 1862418510584, 10109551780216, 54876478924754, 297879564777320, 1616944643352828
OFFSET
1,2
COMMENTS
Column 3 of A317376.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) +12*a(n-2) +15*a(n-3) -42*a(n-4) -28*a(n-5) +16*a(n-6) +4*a(n-7) -41*a(n-8) -5*a(n-9) +66*a(n-10) +45*a(n-11) -2*a(n-12) -50*a(n-13) -12*a(n-14) +12*a(n-15) for n>16
EXAMPLE
Some solutions for n=5
..0..0..1. .0..0..1. .0..1..0. .0..1..0. .0..0..1. .0..0..0. .0..1..1
..1..0..1. .1..0..0. .1..1..1. .1..1..1. .1..1..1. .0..1..0. .0..0..1
..1..0..0. .0..1..0. .1..0..1. .1..0..1. .0..0..1. .1..0..0. .1..1..1
..0..0..1. .0..0..0. .1..0..1. .1..1..1. .1..0..1. .1..0..1. .1..0..0
..0..1..0. .1..1..0. .0..0..0. .0..0..0. .1..1..1. .1..1..1. .1..0..1
CROSSREFS
Cf. A317376.
Sequence in context: A050529 A215613 A306138 * A244632 A042030 A042032
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jul 26 2018
STATUS
approved