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!)
A022284 a(n) = n*(27*n - 1)/2. 2
0, 13, 53, 120, 214, 335, 483, 658, 860, 1089, 1345, 1628, 1938, 2275, 2639, 3030, 3448, 3893, 4365, 4864, 5390, 5943, 6523, 7130, 7764, 8425, 9113, 9828, 10570, 11339, 12135, 12958, 13808, 14685, 15589 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..5000

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

FORMULA

a(n) = a(n-1) + 27*n - 14 for n>0, a(0)=0. - Vincenzo Librandi, Aug 04 2010

G.f.: x*(13 + 14*x)/(1 - x)^3 . - R. J. Mathar, Aug 04 2016

a(n) = A000217(14*n-1) - A000217(13*n-1). - Bruno Berselli, Oct 14 2016

E.g.f.: (x/2)*(27*x + 26)*exp(x). - G. C. Greubel, Aug 23 2017

MATHEMATICA

Table[n (27 n - 1)/2, {n, 0, 40}] (* Bruno Berselli, Oct 14 2016 *)

PROG

(PARI) a(n)=n*(27*n-1)/2 \\ Charles R Greathouse IV, Jun 17 2017

CROSSREFS

Cf. A000217, A022285.

Cf. similar sequences listed in A022288.

Sequence in context: A087880 A228872 A041322 * A179549 A139974 A142188

Adjacent sequences:  A022281 A022282 A022283 * A022285 A022286 A022287

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane

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 February 22 15:05 EST 2020. Contains 332137 sequences. (Running on oeis4.)