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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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified May 25 08:37 EDT 2020. Contains 334587 sequences. (Running on oeis4.)