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!)
A152053 a(n) = A144433(3n+1) + A144433(3n+2) + A144433(3n+3). 0
27, 36, 81, 72, 135, 108, 189, 144, 243, 180, 297, 216, 351, 252, 405, 288, 459, 324, 513, 360, 567, 396, 621, 432, 675, 468, 729, 504, 783, 540, 837, 576, 891, 612, 945, 648, 999, 684, 1053, 720, 1107 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

All terms are multiples of 9.

LINKS

Table of n, a(n) for n=0..40.

Index entries for linear recurrences with constant coefficients, signature (0, 2, 0, -1).

FORMULA

From R. J. Mathar, May 21 2009: (Start)

G.f.: 9*(3+4*x+3*x^2)/((x-1)^2*(1+x)^2).

a(n) = 45*(n+1)/2 + 9*(-1)^n*(n+1)/2. (End)

a(n) = 9*A106833(n+1). - Jean-François Alcover, Feb 02 2019, after Paul Curtz

a(n+4) = 2*a(n+2) - a(n). - Jianing Song, Feb 04 2019

MATHEMATICA

Table[(9/2)(5 + (-1)^n)(n + 1), {n, 0, 40}] (* Jean-François Alcover, Feb 02 2019 *)

LinearRecurrence[{0, 2, 0, -1}, {27, 36, 81, 72}, 50] (* Harvey P. Dale, Nov 07 2019 *)

PROG

(PARI) a(n) = 45*(n+1)/2 + 9*(-1)^n*(n+1)/2 \\ Jianing Song, Feb 04 2019

CROSSREFS

Cf. A106933, A144433.

Sequence in context: A326893 A160119 A160379 * A166649 A025145 A266963

Adjacent sequences:  A152050 A152051 A152052 * A152054 A152055 A152056

KEYWORD

nonn,easy

AUTHOR

Paul Curtz, Nov 22 2008

EXTENSIONS

Edited by R. J. Mathar, May 21 2009

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 June 17 22:14 EDT 2021. Contains 345086 sequences. (Running on oeis4.)