OFFSET
1,1
COMMENTS
Primes of the form x^2 + y^2 + z^2.
LINKS
Ray Chandler, Table of n, a(n) for n = 1..10000 (first 1000 terms from Vincenzo Librandi)
Wikipedia, Legendre's three-square theorem
MATHEMATICA
Select[Prime[Range[300]], MemberQ[{1, 2, 3, 5}, Mod[#, 8]]&] (* Vincenzo Librandi, Aug 08 2012 *)
PROG
(Magma) [p: p in PrimesUpTo(500) | p mod 8 in [1, 2, 3, 5]]; // Vincenzo Librandi, Aug 08 2012
(PARI) is(n)=n%8<6 && isprime(n) \\ Charles R Greathouse IV, Sep 15 2015
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved