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Primes p such that 10*p^3 + 1 is prime.
4

%I #12 Sep 08 2022 08:45:48

%S 3,31,37,43,73,109,163,211,241,313,337,409,499,673,739,757,907,1033,

%T 1039,1069,1237,1327,1447,1483,1489,1597,1663,1741,1777,1933,2083,

%U 2143,2251,2437,2683,2797,3001,3181,3307,3319,3463,3739,3793,4051

%N Primes p such that 10*p^3 + 1 is prime.

%C Subsequence of A168219.

%H G. C. Greubel, <a href="/A168274/b168274.txt">Table of n, a(n) for n = 1..1000</a>

%e 10*3^3+1 = 271 is prime, so prime 3 is in the sequence.

%e 10*313^3+1 = 306642971 is prime, so prime 313 is in the sequence.

%t Select[Prime[Range[100]], PrimeQ[10*#^3 + 1] &] (* _G. C. Greubel_, Jul 16 2016 *)

%o (Magma) [ p: p in PrimesUpTo(5000) | IsPrime(10*p^3+1) ]; // _Vincenzo Librandi_, Jan 29 2011

%o (PARI) select(p->isprime(10*p^3+1), primes(1000)) \\ _Charles R Greathouse IV_, Jul 16 2016

%Y Cf. A168219, A168147.

%K nonn

%O 1,1

%A Eva-Maria Zschorn (e-m.zschorn(AT)zaschendorf.km3.de), Nov 22 2009

%E Edited by _Charles R Greathouse IV_, Apr 24 2010