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!)
A021824 Expansion of 1/((1-x)(1-4x)(1-6x)(1-9x)). 1
1, 20, 267, 3010, 31073, 304920, 2901319, 27075950, 249555405, 2281579300, 20749095731, 188036746170, 1700122392697, 15347941075760, 138412864844703, 1247405586235270, 11236794818538149, 101192043527859900 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
LINKS
FORMULA
G.f.: 1/((1-x)(1-4x)(1-6x)(1-9x)).
a(n) = (9^(n+3) - 4*6^(n+3) + 4^(n+4) - 1)/120. - Yahia Kahloune, Jul 05 2013
MATHEMATICA
CoefficientList[Series[1 / ((1 - x) (1 - 4 x) (1 - 6 x) (1 - 9 x)), {x, 0, 20}], x] (* Vincenzo Librandi, Jul 11 2013 *)
CROSSREFS
Sequence in context: A021854 A025939 A278773 * A125455 A019928 A025934
KEYWORD
nonn,easy
AUTHOR
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 20 11:40 EDT 2024. Contains 371838 sequences. (Running on oeis4.)