login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A242234 Number of length n+3+1 0..3 arrays with every value 0..3 appearing at least once in every consecutive 3+2 elements, and new values 0..3 introduced in order. 2
10, 22, 43, 82, 157, 304, 586, 1129, 2176, 4195, 8086, 15586, 30043, 57910, 111625, 215164, 414742, 799441, 1540972, 2970319, 5725474, 11036206, 21272971, 41004970, 79039621, 152353768, 293671330, 566069689, 1091134408, 2103229195, 4054104622 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A242239.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +a(n-2) +a(n-3) +a(n-4).

Conjecture: a(n) = 9*A145112(n-1) + A016777(n-1). - R. J. Mathar, Aug 16 2017

Empirical g.f.: x*(10 + 12*x + 11*x^2 + 7*x^3) / (1 - x - x^2 - x^3 - x^4). - Colin Barker, Mar 19 2018

EXAMPLE

Some solutions for n=5:

..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0

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

..1....2....2....2....2....1....2....0....1....0....1....2....2....2....2....0

..2....1....3....3....0....2....3....2....2....2....2....0....0....3....1....2

..3....3....0....0....3....3....0....3....3....3....3....3....3....0....3....3

..0....0....1....3....1....0....2....0....0....0....0....1....2....1....0....1

..2....2....2....1....2....0....1....1....1....1....1....2....1....2....2....3

..1....1....3....2....2....1....2....1....2....2....1....0....0....3....0....0

..1....3....0....2....0....2....3....2....1....3....2....2....0....3....1....2

CROSSREFS

Cf. A016777, A145112, A242239.

Sequence in context: A014367 A063710 A157917 * A104867 A179877 A216048

Adjacent sequences:  A242231 A242232 A242233 * A242235 A242236 A242237

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 08 2014

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 9 07:36 EDT 2021. Contains 343692 sequences. (Running on oeis4.)