

A045327


Primes congruent to {2, 3, 4} mod 5.


6



2, 3, 7, 13, 17, 19, 23, 29, 37, 43, 47, 53, 59, 67, 73, 79, 83, 89, 97, 103, 107, 109, 113, 127, 137, 139, 149, 157, 163, 167, 173, 179, 193, 197, 199, 223, 227, 229, 233, 239, 257, 263, 269, 277, 283, 293, 307
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OFFSET

1,1


COMMENTS

This sequence also happens to be one of impossible prime factors of 2^(2^n)+7. To form the sequence one uses pari {p(n) =(2^(2^n) + 7)/p} and the run the program up to only Eulerphi(Eulerphi(p)). [From A.K. Devaraj, Dec 14 2009]


LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000


FORMULA

a(n) ~ (4/3) n log n.  Charles R Greathouse IV, Aug 07 2012


MATHEMATICA

Select[Prime[Range[300]], MemberQ[{2, 3, 4}, Mod[#, 5]]&] (* Vincenzo Librandi, Aug 07 2012 *)


PROG

(MAGMA) [ p: p in PrimesUpTo(600)  p mod 5 in {2, 3, 4} ]; // Vincenzo Librandi, Aug 07 2012
(PARI) select(n>n%5>1, primes(50)) \\ Charles R Greathouse IV, Aug 07 2012


CROSSREFS

Cf. A000040.
Sequence in context: A225098 A101739 A141633 * A181103 A329487 A220814
Adjacent sequences: A045324 A045325 A045326 * A045328 A045329 A045330


KEYWORD

nonn,easy


AUTHOR

N. J. A. Sloane.


STATUS

approved



