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!)
A255994 Number of length n+3 0..1 arrays with at most one downstep in every n consecutive neighbor pairs. 1
16, 32, 53, 80, 114, 156, 207, 268, 340, 424, 521, 632, 758, 900, 1059, 1236, 1432, 1648, 1885, 2144, 2426, 2732, 3063, 3420, 3804, 4216, 4657, 5128, 5630, 6164, 6731, 7332, 7968, 8640, 9349, 10096, 10882, 11708, 12575, 13484, 14436, 15432, 16473, 17560 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Row 3 of A255992.
LINKS
FORMULA
Empirical: a(n) = (1/6)*n^3 + (3/2)*n^2 + (31/3)*n + 4.
Empirical g.f.: x*(16 - 32*x + 21*x^2 - 4*x^3) / (1 - x)^4. - Colin Barker, Jan 25 2018
EXAMPLE
Some solutions for n=4:
..0....1....0....0....1....0....1....0....1....1....0....0....1....1....0....0
..1....1....0....0....1....1....1....0....0....1....1....1....1....0....1....0
..0....0....0....0....1....0....0....1....0....1....1....1....1....1....0....1
..1....0....1....1....0....0....0....1....0....1....1....0....0....1....0....1
..1....0....0....0....0....0....1....1....0....1....0....0....0....1....0....0
..1....0....0....0....1....0....1....0....1....1....0....0....0....1....1....0
..1....0....1....0....1....1....1....0....1....1....1....0....0....1....1....0
CROSSREFS
Cf. A255992.
Sequence in context: A048946 A260050 A224544 * A204645 A236323 A018923
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 13 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 | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 16 18:22 EDT 2024. Contains 371750 sequences. (Running on oeis4.)