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Primes p such that 2*p-3 and 4*p-5 are also prime.
1

%I #8 Sep 08 2022 08:45:51

%S 3,7,13,43,67,97,127,181,211,223,331,373,457,613,727,751,757,907,967,

%T 1021,1033,1171,1201,1231,1453,1471,1483,1747,1933,2011,2137,2437,

%U 2473,2503,2521,2617,2857,2953,3067,3163,3541,3607,3823,3847,3943,4057,5167

%N Primes p such that 2*p-3 and 4*p-5 are also prime.

%H Vincenzo Librandi, <a href="/A174241/b174241.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Prime[Range[500]], PrimeQ[2 # - 3] && PrimeQ[4 # - 5] &] (* _Vincenzo Librandi_, Apr 10 2013 *)

%o (Magma) [p: p in PrimesUpTo(7000) | IsPrime(4*p-5) and IsPrime(2*p-3)];

%K nonn,easy

%O 1,1

%A _Vincenzo Librandi_, Mar 13 2010