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A045327 Primes congruent to {2, 3, 4} mod 5. 6

%I

%S 2,3,7,13,17,19,23,29,37,43,47,53,59,67,73,79,83,89,97,103,107,109,

%T 113,127,137,139,149,157,163,167,173,179,193,197,199,223,227,229,233,

%U 239,257,263,269,277,283,293,307

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

%C 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]

%H Vincenzo Librandi, <a href="/A045327/b045327.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) ~ (4/3) n log n. - _Charles R Greathouse IV_, Aug 07 2012

%t Select[Prime[Range[300]],MemberQ[{2,3,4},Mod[#,5]]&] (* _Vincenzo Librandi_, Aug 07 2012 *)

%o (MAGMA) [ p: p in PrimesUpTo(600) | p mod 5 in {2, 3, 4} ]; // _Vincenzo Librandi_, Aug 07 2012

%o (PARI) select(n->n%5>1, primes(50)) \\ _Charles R Greathouse IV_, Aug 07 2012

%Y Cf. A000040.

%K nonn,easy

%O 1,1

%A _N. J. A. Sloane_.

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Last modified July 6 23:56 EDT 2020. Contains 335484 sequences. (Running on oeis4.)