OFFSET
1,1
COMMENTS
Conjecture: a(n) <= prime(n). Tested to n=10000.
LINKS
T. D. Noe, Table of n, a(n) for n = 1..10000
EXAMPLE
Prime(1)*2-2=2 is prime, so a(1)=2;
Prime(2)*3-2=7 is prime, so a(2)=3;
MATHEMATICA
Table[p=Prime[n]; k=1; pk=Prime[k]; cp=p*pk-2; While[ !PrimeQ[cp], k=k+1; pk=Prime[k]; cp=p*pk-2]; pk, {n, 100}]
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Lei Zhou, Feb 22 2005
STATUS
approved