login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A140325 Binomial(n+8,8) * 2^n. 12
1, 18, 180, 1320, 7920, 41184, 192192, 823680, 3294720, 12446720, 44808192, 154791936, 515973120, 1666990080, 5239111680, 16066609152, 48199827456, 141764198400, 409541017600, 1163958681600, 3259084308480, 9001280471040 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

With a different offset, number of n-permutations (n>=8) of 3 objects: u, v, z with repetition allowed, containing exactly eight (8) u's. See example.

Number of 8D hypercubes in an n-dimensional hypercube. [Zerinvary Lajos, Jan 29 2010]

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..400

M. Janjic and B. Petkovic, A Counting Function, arXiv 1301.4550, 2013

FORMULA

G.f.: 1/(1-2*x)^9. [R. J. Mathar, Feb 11 2010]

a(n) = 2*a(n-1) + A054851(n-1). [Ruskin Harding, May 12 2013]

EXAMPLE

Example: a(1)=18 because we have uuuuuuuuv, uuuuuuuvu, uuuuuuvuu, uuuuuvuuu, uuuuvuuuu, uuuvuuuuu, uuvuuuuuu, uvuuuuuuu, vuuuuuuuu, uuuuuuuuz, uuuuuuuzu, uuuuuuzuu, uuuuuzuuu, uuuuzuuuu, uuuzuuuuu, uuzuuuuuu, uzuuuuuuu and zuuuuuuu.

MAPLE

seq(binomial(n+8, 8)*2^n, n=0..28);

MATHEMATICA

Table[Binomial[n + 8, 8]*2^n, {n, 0, 20}] (* Zerinvary Lajos, Jan 29 2010 *)

PROG

(Sage) [lucas_number2(n, 2, 0)*binomial(n, 8)/256 for n in xrange(8, 30)] [Zerinvary Lajos, Mar 10 2009]

(MAGMA) [2^n* Binomial(n+8, 8): n in [0..30]]; // Vincenzo Librandi, Oct 14 2011

CROSSREFS

Sequence in context: A071910 A121038 A004410 * A199299 A155669 A160954

Adjacent sequences:  A140322 A140323 A140324 * A140326 A140327 A140328

KEYWORD

nonn,easy

AUTHOR

Zerinvary Lajos, Jun 23 2008

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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified June 25 22:15 EDT 2017. Contains 288730 sequences.