A317692 Number of nX3 0..1 arrays with every element unequal to 0, 1, 3, 4, 5, 6, 7 or 8 king-move adjacent elements, with upper left element zero.

3, 9, 14, 33, 92, 220, 593, 1787, 5401, 16954, 55199, 182686, 613262, 2081449, 7111645, 24412407, 84069938, 290115461, 1002577520, 3467926870, 12002906321, 41560738593, 143945514141, 498643272858, 1727563137885, 5985662474410

Offset

1,1

Comments

Column 3 of A317697.

Links

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

Formula

Empirical: a(n) = 5*a(n-1) -6*a(n-2) +16*a(n-3) -60*a(n-4) +43*a(n-5) -36*a(n-6) +156*a(n-7) -49*a(n-8) -12*a(n-9) -91*a(n-10) +28*a(n-11) -94*a(n-12) -121*a(n-13) +362*a(n-14) -148*a(n-15) -28*a(n-16) +16*a(n-17) for n>19

Example

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

Crossrefs

Cf. A317697.

Sequence in context: A316422 A100785 A317038 * A175351 A332660 A343144

Adjacent sequences: A317689 A317690 A317691 * A317693 A317694 A317695

Keyword

nonn

Author

R. H. Hardin, Aug 04 2018

Status

approved