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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A048756 Prime repunits in ascending prime bases (written in decimal). 0
3, 13, 305175781 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

2^2-1=3 is prime; (3^3-1)/2=13 is prime; (5^13-1)/4=305175781 is prime; the next term is too gigantic to be computed simply.

LINKS

Table of n, a(n) for n=1..3.

FORMULA

a(p)=((p^a(p-1))-1)/(p-1); a(p)=111...111 in base p with a(p-1) 1's; p runs though the primes.

CROSSREFS

Sequence in context: A317481 A271393 A087345 * A174211 A264611 A157323

Adjacent sequences:  A048753 A048754 A048755 * A048757 A048758 A048759

KEYWORD

nonn,bref

AUTHOR

Xavier Labouze (Xavier.Labouze(AT)cep.u-psud.fr)

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 January 22 11:52 EST 2019. Contains 319363 sequences. (Running on oeis4.)