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!)
A255656 Number of length n+4 0..3 arrays with at most two downsteps in every 4 consecutive neighbor pairs 1
968, 3692, 14192, 54560, 209412, 803246, 3083292, 11835664, 45429680, 174365744, 669261344, 2568836929, 9859943512, 37845226102, 145260624176, 557551963747, 2140043779888, 8214097736920, 31528047115872, 121013635650740 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A255660

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) -4*a(n-3) +15*a(n-4) -24*a(n-5) -68*a(n-6) +136*a(n-7) -81*a(n-8) +40*a(n-9) -10*a(n-10) +4*a(n-11) -a(n-12)

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

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

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

CROSSREFS

Cf. A255660

Sequence in context: A064258 A142378 A035887 * A035759 A107555 A175991

Adjacent sequences:  A255653 A255654 A255655 * A255657 A255658 A255659

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 01 2015

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 October 17 21:17 EDT 2021. Contains 348065 sequences. (Running on oeis4.)