OFFSET
1,2
LINKS
T. D. Noe, Table of n, a(n) for n = 1..1000
FORMULA
a(n) = (A081759(n)+1)/2.
MATHEMATICA
Select[Range[170], PrimeQ[10# + 1] &] (* Ray Chandler, Dec 06 2006 *)
PROG
(Magma) [n: n in [1..1000] |IsPrime(10*n+1)]; // Vincenzo Librandi, Nov 19 2010
(PARI) is(n)=isprime(10*n+1) \\ Charles R Greathouse IV, Jul 02 2013
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved