A301356 Number of nX3 0..1 arrays with every element equal to 1, 2, 4, 5 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

1, 6, 13, 34, 92, 256, 721, 2036, 5701, 15848, 43916, 121825, 338722, 943311, 2628900, 7326706, 20413096, 56853677, 158313447, 440815860, 1227496584, 3418358547, 9520049340, 26513664655, 73841105634, 205645969535, 572712412815

Offset

1,2

Comments

Column 3 of A301361.

Links

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

Formula

Empirical: a(n) = 8*a(n-1) -26*a(n-2) +47*a(n-3) -60*a(n-4) +74*a(n-5) -85*a(n-6) +71*a(n-7) -68*a(n-8) +56*a(n-9) -10*a(n-10) +72*a(n-11) -8*a(n-12) -148*a(n-13) -108*a(n-14) -6*a(n-15) +182*a(n-16) +168*a(n-17) +76*a(n-18) -38*a(n-19) -60*a(n-20) -64*a(n-21) -62*a(n-22) +49*a(n-24) +28*a(n-25) -10*a(n-26) -17*a(n-27) -2*a(n-28) +6*a(n-29) +a(n-30) -a(n-31)

Example

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

Crossrefs

Cf. A301361.

Sequence in context: A041068 A300430 A300634 * A037243 A107710 A114689

Adjacent sequences: A301353 A301354 A301355 * A301357 A301358 A301359

Keyword

nonn

Author

R. H. Hardin, Mar 19 2018

Status

approved