OFFSET
0,1
LINKS
Pierre CAMI, Table of n, a(n) for n = 0..500
EXAMPLE
3*2*2^0-1=5 is prime so for n=0 p=2.
3*2*2^1-1=11 is prime so for n=1 p=2.
PROG
(PARI) a(n) = my(p=2); while (!isprime(3*p*2^n-1), p=nextprime(p+1)); p; \\ Michel Marcus, Sep 23 2019
CROSSREFS
KEYWORD
nonn
AUTHOR
Pierre CAMI, May 24 2007
STATUS
approved