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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A153780 10 times pentagonal numbers: a(n) = 5*n*(3*n-1). 0
0, 10, 50, 120, 220, 350, 510, 700, 920, 1170, 1450, 1760, 2100, 2470, 2870, 3300, 3760, 4250, 4770, 5320, 5900, 6510, 7150, 7820, 8520, 9250, 10010, 10800, 11620, 12470, 13350, 14260, 15200, 16170, 17170, 18200, 19260, 20350 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..37.

FORMULA

a(n) = 15n^2 - 5n = A000326(n)*10 = A049450(n)*5 = A152734(n)*2.

a(n) = 30*n+a(n-1)-20 for n>0, a(0)=0. [Vincenzo Librandi, Aug 03 2010]

G.f.: 10*x*(1+2*x)/(1-x)^3. [Colin Barker, Feb 14 2012]

CROSSREFS

Cf. A000326, A049450, A152734, A152996, A153449.

Sequence in context: A036786 A085444 A102915 * A196507 A008531 A051230

Adjacent sequences:  A153777 A153778 A153779 * A153781 A153782 A153783

KEYWORD

nonn,easy

AUTHOR

Omar E. Pol, Jan 01 2009

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified March 27 03:02 EDT 2015. Contains 255920 sequences.