login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A283852 Number of n X 3 0..1 arrays with no 1 equal to more than three of its horizontal, diagonal and antidiagonal neighbors. 1
8, 61, 409, 2837, 19776, 137459, 955680, 6645662, 46211001, 321328965, 2234376733, 15536845232, 108036163039, 751234447860, 5223743482218, 36323541679065, 252577425569649, 1756308801126965, 12212574412144160, 84920700547463563 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

Empirical: a(n) = 7*a(n-1) - 2*a(n-2) + 19*a(n-3) - 50*a(n-4) - 2*a(n-5) - 48*a(n-6) + 88*a(n-7) - 32*a(n-8).

Empirical g.f.: x*(8 + 5*x - 2*x^2 - 56*x^3 - 24*x^4 - 4*x^5 + 72*x^6 - 32*x^7) / (1 - 7*x + 2*x^2 - 19*x^3 + 50*x^4 + 2*x^5 + 48*x^6 - 88*x^7 + 32*x^8). - Colin Barker, Feb 22 2019

EXAMPLE

Some solutions for n=4:

..1..1..0. .1..0..1. .1..1..0. .0..0..0. .1..0..1. .1..0..0. .1..1..1

..0..1..0. .0..0..0. .0..1..0. .0..1..0. .0..0..1. .1..1..0. .0..0..1

..1..1..0. .1..1..1. .0..0..1. .1..1..0. .0..1..1. .0..0..0. .1..0..1

..0..0..1. .0..1..1. .0..1..1. .1..1..1. .1..0..0. .1..1..0. .0..0..1

CROSSREFS

Column 3 of A283857.

Sequence in context: A007399 A071401 A247535 * A283410 A081907 A278596

Adjacent sequences:  A283849 A283850 A283851 * A283853 A283854 A283855

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 17 2017

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 19 18:35 EDT 2022. Contains 353847 sequences. (Running on oeis4.)