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Numbers n such that 191*n + 193 is prime.
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%I #15 Sep 08 2022 08:45:19

%S 0,8,18,20,30,36,38,44,50,56,66,74,78,80,86,90,98,116,144,150,156,164,

%T 174,176,198,200,204,230,234,260,284,288,300,308,314,326,350,354,366,

%U 368,408,426,450,458,464,470,480,494,498,504,518,540,546,570,588,594

%N Numbers n such that 191*n + 193 is prime.

%C 191 and 193 are twin primes.

%H Chris Caldwell, <a href="http://www.utm.edu/research/primes/lists/small/1ktwins.txt">The First 1,008 Twin Primes</a>.

%e If n=56, then 191*n + 193 = 10889 (prime).

%t Select[Range[0,1000],PrimeQ[191#+193]&] (* _Harvey P. Dale_, Dec 26 2010 *)

%o (Magma) [n: n in [0..100000] | IsPrime(191*n + 193)] // _Vincenzo Librandi_, Nov 13 2010

%o (PARI) is(n)=isprime(191*n+193) \\ _Charles R Greathouse IV_, Jun 13 2017

%K nonn,easy

%O 1,2

%A _Parthasarathy Nambi_, Jun 02 2005