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Numbers k such that k211 is prime.
7

%I #25 Sep 08 2022 08:45:16

%S 0,4,6,7,10,12,18,19,21,27,28,30,33,34,49,58,61,63,67,72,75,84,87,88,

%T 96,105,108,109,111,115,118,126,130,135,142,147,150,154,157,163,165,

%U 168,175,177,180,181,184,186,187,199,201,205,214,216,223,228,234,235,249,256,258,259,264,268,271,279

%N Numbers k such that k211 is prime.

%C Also numbers k such that 1000*k+211 is prime. - _Stefan Steinerberger_, Feb 12 2006

%H Harvey P. Dale, <a href="/A103401/b103401.txt">Table of n, a(n) for n = 1..1000</a>

%e If k=27, then k211 = 27211 (prime).

%e If k=72, then k211 = 72211 (prime).

%t For[n = 0, n < 220, n++, If[PrimeQ[1000*n + 211], Print[n]]] (* _Stefan Steinerberger_, Feb 12 2006 *)

%t Select[Range[0,300],PrimeQ[1000#+211]&] (* _Harvey P. Dale_, Dec 14 2021 *)

%o (Magma) [ n: n in [0..700] | IsPrime(Seqint([1, 1, 2] cat Intseq(n))) ]; // _Vincenzo Librandi_, Feb 03 2011

%Y Cf. A103118, A102624.

%K base,nonn

%O 1,2

%A _Parthasarathy Nambi_, Mar 20 2005

%E More terms from _Stefan Steinerberger_, Feb 12 2006