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!)
A050522 Primes of form 5*2^n-1. 5
19, 79, 1279, 5119, 20479, 81919, 1310719, 21474836479, 1407374883553279, 90071992547409919, 23611832414348226068479, 1784059615882449851322857461811868920478433279 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Heiko Harborth, On h-perfect numbers, Annales Mathematicae et Informaticae, 41 (2013) pp. 57-62.
FORMULA
a(n) = 5*2^A001770(n) - 1. - Max Alekseyev, Feb 20 2024
MATHEMATICA
Select[Table[5*2^n-1, {n, 0, 150}], PrimeQ] (* Jean-François Alcover, Mar 21 2011 *)
CROSSREFS
See A001770 for more terms.
Sequence in context: A139941 A127270 A053665 * A366965 A172973 A212056
KEYWORD
nonn,nice
AUTHOR
N. J. A. Sloane, Dec 29 1999
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 July 24 18:12 EDT 2024. Contains 374585 sequences. (Running on oeis4.)