OFFSET
1,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
EXAMPLE
1 is a member because 210*1+1=211 is prime; 100 is a member because 210*100+1=21001 is prime.
MATHEMATICA
Flatten[Position[PrimeQ[210Range[100]+1], True]]
Select[Range[150], PrimeQ[(210*# + 1)] &] (* Vincenzo Librandi, Sep 30 2012 *)
PROG
(Magma) [n: n in [1..200] | IsPrime(210*n + 1)]; Vincenzo Librandi, Sep 30 2012
(PARI) is(n)=isprime(210*n+1) \\ Charles R Greathouse IV, May 22 2017
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Zak Seidov, Oct 08 2002
STATUS
approved