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.

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

R. H. Hardin, Table of n, a(n) for n = 1..210

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

Adjacent sequences: A305014 A305015 A305016 * A305018 A305019 A305020

Keyword

nonn

Author

R. H. Hardin, May 23 2018

Status

approved