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Primes p such that 2*p^3-1 is also prime.
9

%I #14 Sep 08 2022 08:45:53

%S 3,31,43,61,139,181,199,223,241,331,373,421,523,631,733,859,991,1033,

%T 1153,1213,1423,1453,1549,1741,1873,1879,1951,2203,2239,2269,2311,

%U 2371,2539,2689,2713,2719,2851,3001,3019,3163,3229,3271,3343,3361,3391,3541

%N Primes p such that 2*p^3-1 is also prime.

%H Vincenzo Librandi, <a href="/A177104/b177104.txt">Table of n, a(n) for n = 1..1000</a>

%F A000040 INTERSECT A214289. - _R. J. Mathar_, Aug 20 2019

%t Select[Prime[Range[500]], PrimeQ[2 #^3 - 1]&] (* _Vincenzo Librandi_, Apr 17 2013 *)

%o (Magma) [p: p in PrimesUpTo(10000)| IsPrime(2*p^3-1)];

%K nonn,easy

%O 1,1

%A _Vincenzo Librandi_, Nov 15 2010