OFFSET
1,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
FORMULA
a(n) = 2*A023204(n) + 3.
MATHEMATICA
Clear[lst, n, f] f[n_]:=PrimeQ[(n-3)/2]; lst={}; Do[p=Prime[n]; If[f[p], AppendTo[lst, p]], {n, 6!}]; lst (* Vladimir Joseph Stephan Orlovsky, Oct 13 2009 *)
Select[Prime[Range[300]], PrimeQ[(# - 3) / 2]&] (* Vincenzo Librandi, Apr 13 2013 *)
PROG
(Magma) [p: p in PrimesUpTo(1300) | IsPrime((p-3) div 2)]; // Vincenzo Librandi, Apr 13 2013
(PARI) is(n)=isprime(n) && isprime((n-3)\2) \\ Charles R Greathouse IV, Sep 09 2014
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Ray Chandler, Nov 07 2003
EXTENSIONS
Comment from Juri-Stepan Gerasimov used as new name (old name moved to formulas). - Charles R Greathouse IV, Sep 09 2014
STATUS
approved