A274897 Number of 5 X n 0..2 arrays with no element equal to any value at offset (0,-1) (-1,-1) or (-2,0) and new values introduced in order 0..2.

12, 26, 84, 275, 913, 3064, 10337, 34921, 117975, 398560, 1346637, 4550382, 15376372, 51958316, 175571071, 593268299, 2004704682, 6774075554, 22890197334, 77347965186, 261365481435, 883176688023, 2984330940525, 10084314105326

Offset

1,1

Links

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

Formula

Empirical: a(n) = 8*a(n-1) - 27*a(n-2) + 56*a(n-3) - 75*a(n-4) + 61*a(n-5) - 28*a(n-6) + 7*a(n-7) - a(n-8) for n>9.

Empirical g.f.: x*(12 - 70*x + 200*x^2 - 367*x^3 + 425*x^4 - 301*x^5 + 126*x^6 - 30*x^7 + 4*x^8) / ((1 - x)^3*(1 - 5*x + 9*x^2 - 13*x^3 + 4*x^4 - x^5)). - Colin Barker, Jan 31 2019

Example

Some solutions for n=4:
..0..1..2..1. .0..1..2..0. .0..1..0..1. .0..1..2..1. .0..1..2..0
..1..2..0..1. .0..1..2..0. .1..2..0..1. .0..2..0..1. .1..2..0..1
..1..0..1..2. .1..2..0..1. .1..0..1..2. .1..2..1..2. .2..0..1..2
..2..0..1..2. .2..0..1..2. .2..0..2..0. .1..0..1..0. .0..1..2..0
..2..1..2..0. .2..1..2..0. .0..1..2..0. .2..0..2..0. .0..1..0..1

Crossrefs

Row 5 of A274895.

Sequence in context: A357893 A211115 A232936 * A030736 A227854 A003346

Adjacent sequences: A274894 A274895 A274896 * A274898 A274899 A274900

Keyword

nonn

Author

R. H. Hardin, Jul 10 2016

Status

approved