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!)
A015486 a(0)=1, a(1)=2, a(n) = sum_{k=0}^{k=n-1} 2^k a(k). 1
1, 2, 5, 25, 225, 3825, 126225, 8204625, 1058396625, 272007932625, 139540069436625, 143028571172540625, 293065542332535740625, 1200689526936398929340625, 9837249294189916428087740625, 161183329685301780674217630140625 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
LINKS
PROG
(Magma) I:=[1, 2, 5]; [n le 3 select I[n] else (2^(n-2)+1)*Self(n-1): n in [1..18]]; // Vincenzo Librandi, Nov 10 2012
CROSSREFS
Sequence in context: A049650 A191506 A139007 * A191951 A356674 A370555
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 March 18 22:56 EDT 2024. Contains 370952 sequences. (Running on oeis4.)