OFFSET
1,1
COMMENTS
The sequence of repunit primes is a subsequence of this sequence.
LINKS
Ray Chandler, Table of n, a(n) for n = 1..96
Makoto Kamada, Factorizations of 11...11 (Repunit).
FORMULA
EXAMPLE
prime(15)=47 and (10^47-1)/9 = 35121409*316362908763458525001406154038726382279, so a(15)=35121409.
CROSSREFS
KEYWORD
nonn
AUTHOR
Farideh Firoozbakht, Dec 26 2008
EXTENSIONS
Edited by Ray Chandler, Apr 06 2011
STATUS
approved