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A305017
Number of nX3 0..1 arrays with every element unequal to 2, 3, 4, 5 or 7 king-move adjacent elements, with upper left element zero.
2
0, 5, 14, 73, 387, 2000, 10487, 54957, 287218, 1503959, 7869877, 41184270, 215540219, 1127976673, 5903110936, 30893060733, 161673863609, 846095754528, 4427911443157, 23172791974003, 121271244926878, 634654381325531
OFFSET
1,2
COMMENTS
Column 3 of A305022.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) +14*a(n-2) +6*a(n-3) -79*a(n-4) -104*a(n-5) +77*a(n-6) +181*a(n-7) +65*a(n-8) -51*a(n-9) -5*a(n-10) +49*a(n-11) +5*a(n-12) -18*a(n-13) -2*a(n-14) +4*a(n-15) for n>16
EXAMPLE
Some solutions for n=5
..0..1..0. .0..0..0. .0..1..0. .0..1..0. .0..1..1. .0..0..1. .0..1..0
..0..1..1. .1..1..1. .0..1..1. .0..1..1. .1..0..0. .1..1..0. .1..0..1
..1..0..0. .1..0..0. .0..0..1. .0..0..1. .1..0..1. .1..1..1. .0..0..1
..0..0..1. .0..1..0. .1..1..0. .1..0..1. .0..1..1. .0..0..0. .0..1..1
..1..0..1. .1..0..1. .0..1..0. .0..1..0. .0..1..0. .1..0..1. .0..1..0
CROSSREFS
Cf. A305022.
Sequence in context: A202764 A197876 A370761 * A007838 A306751 A305341
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 23 2018
STATUS
approved