OFFSET
1,1
COMMENTS
FORMULA
a(n) = precprime(10^n/3) = A007917((10^n-1)/3). - Max Alekseyev, Sep 29 2015
EXAMPLE
a(1)=31 because it is the largest factor of odd N <= 10^2-1. The value of odd N where this factor first occurs is 3*31 = 93.
PROG
(PARI) a(n)=precprime(10^n\3)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Enoch Haga, Dec 12 2007
EXTENSIONS
Clarified and extended by Charles R Greathouse IV, Oct 11 2009
STATUS
approved