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

 

Logo

Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing.
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A011779 Expansion of 1/((1-x)^3*(1-x^3)^2). 4
1, 3, 6, 12, 21, 33, 51, 75, 105, 145, 195, 255, 330, 420, 525, 651, 798, 966, 1162, 1386, 1638, 1926, 2250, 2610, 3015, 3465, 3960, 4510, 5115, 5775, 6501, 7293, 8151, 9087, 10101, 11193, 12376, 13650 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

The Ca2 and Ze4 triangle sums of A139600 are related to the sequence given above, e.g., Ze4(n) = A011779(n-1) - A011779(n-2) - A011779(n-4) + 3*A011779(n-5), with A011779(n) = 0 for n <= -1. For the definitions of these triangle sums see A180662. [Johannes W. Meijer, Apr 29 2011]

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (3,-3,3,-6,6,-3,3,-3,1).

MATHEMATICA

CoefficientList[Series[1 / ((1 - x)^3 (1 - x^3)^2), {x, 0, 100}], x] (* Vincenzo Librandi, Jun 23 2013 *)

PROG

(PARI) Vec(1/((1-x)^3*(1-x^3)^2)+O(x^99)) \\ Charles R Greathouse IV, Sep 25 2012

CROSSREFS

Cf. A236770 (first trisection, except 0).

Sequence in context: A053479 A290768 A070333 * A161809 A084439 A034344

Adjacent sequences:  A011776 A011777 A011778 * A011780 A011781 A011782

KEYWORD

nonn,easy

AUTHOR

Emeric Deutsch

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 December 15 22:02 EST 2019. Contains 330012 sequences. (Running on oeis4.)