A317031 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 4, 5, 6 or 8 king-move adjacent elements, with upper left element zero.

4, 14, 30, 82, 280, 842, 2591, 8141, 25387, 79075, 247002, 771516, 2408705, 7522325, 23494122, 73374104, 229158274, 715707738, 2235297120, 6981287296, 21804026411, 68098596051, 212686440221, 664265316611, 2074643216856, 6479557040796

Offset

1,1

Comments

Column 3 of A317036.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +4*a(n-2) +8*a(n-3) -13*a(n-4) -45*a(n-5) -55*a(n-6) +30*a(n-7) +163*a(n-8) +194*a(n-9) +12*a(n-10) -223*a(n-11) -209*a(n-12) -51*a(n-13) +37*a(n-14) +3*a(n-15) for n>17

Example

Some solutions for n=5
..0..1..0. .0..0..0. .0..1..1. .0..0..0. .0..1..1. .0..1..0. .0..1..0
..0..0..0. .0..0..0. .0..1..1. .0..0..1. .0..1..1. .0..0..1. .0..0..0
..1..0..0. .1..0..0. .0..0..0. .0..0..0. .1..1..1. .0..0..0. .0..0..1
..1..0..0. .1..0..0. .0..0..0. .0..0..0. .1..1..1. .0..0..0. .0..0..1
..0..0..0. .1..1..1. .0..0..0. .0..1..1. .0..0..1. .0..0..0. .0..0..0

Crossrefs

Cf. A317036.

Sequence in context: A049451 A079776 A117109 * A140063 A051409 A072475

Adjacent sequences: A317028 A317029 A317030 * A317032 A317033 A317034

Keyword

nonn

Author

R. H. Hardin, Jul 19 2018

Status

approved