

A045331


Primes congruent to {1, 2, 3} mod 6; or, 3 is a square mod p.


13



2, 3, 7, 13, 19, 31, 37, 43, 61, 67, 73, 79, 97, 103, 109, 127, 139, 151, 157, 163, 181, 193, 199, 211, 223, 229, 241, 271, 277, 283, 307, 313, 331, 337, 349, 367, 373, 379, 397, 409, 421, 433, 439, 457, 463, 487, 499, 523, 541, 547, 571, 577, 601, 607, 613
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OFFSET

1,1


COMMENTS

3 is a quadratic residue mod a prime p iff p is in this sequence.


LINKS



MATHEMATICA

Select[Prime[Range[200]], MemberQ[{1, 2, 3}, Mod[#, 6]]&] (* Harvey P. Dale, Mar 31 2011 *)
Join[{2, 3}, Select[Range[7, 10^3, 6], PrimeQ]] (* Zak Seidov, May 20 2011 *)


PROG

(Magma) [p: p in PrimesUpTo(700)  p mod 6 in [1, 2, 3]]; // Vincenzo Librandi, Aug 08 2012
(Haskell)
a045331 n = a045331_list !! (n1)
a045331_list = filter ((< 4) . (`mod` 6)) a000040_list


CROSSREFS

Apart from initial term, same as A007645; apart from initial two terms, same as A002476.


KEYWORD

nonn,nice,easy


AUTHOR



EXTENSIONS



STATUS

approved



