A316643 Number of nX3 0..1 arrays with every element unequal to 1, 2, 4, 5, 7 or 8 king-move adjacent elements, with upper left element zero.

1, 11, 15, 33, 117, 247, 599, 1757, 4241, 10783, 29239, 74521, 192273, 508375, 1317567, 3422449, 8971629, 23370303, 60880867, 159136445, 415145389, 1082772235, 2827552935, 7379387077, 19255943685, 50269166119, 131207698359

Offset

1,2

Comments

Column 3 of A316648.

Links

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

Formula

Empirical: a(n) = a(n-1) +4*a(n-2) +13*a(n-3) -13*a(n-4) -46*a(n-5) -59*a(n-6) +53*a(n-7) +153*a(n-8) +98*a(n-9) -60*a(n-10) -140*a(n-11) -7*a(n-12) +67*a(n-13) +15*a(n-14) -78*a(n-15) -48*a(n-16) -32*a(n-17)

Example

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

Crossrefs

Cf. A316648.

Sequence in context: A275242 A030099 A085597 * A097512 A032490 A068483

Adjacent sequences: A316640 A316641 A316642 * A316644 A316645 A316646

Keyword

nonn

Author

R. H. Hardin, Jul 09 2018

Status

approved