OFFSET
1,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
FORMULA
a(n) ~ 12n log n. - Charles R Greathouse IV, Jul 03 2016
MATHEMATICA
Select[Prime[Range[500]], MemberQ[{3}, Mod[#, 28]] &] (* Vincenzo Librandi, Aug 16 2012 *)
Select[Range[3, 4000, 28], PrimeQ] (* Harvey P. Dale, Jul 07 2016 *)
PROG
(Magma) [p: p in PrimesUpTo(5000) | p mod 28 eq 3 ]; // Vincenzo Librandi, Aug 16 2012
(PARI) is(n)=isprime(n) && n%28==3 \\ Charles R Greathouse IV, Jul 03 2016
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Jul 11 2008
STATUS
approved