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Primes p such that 2p - 3 and 2p - 1 are twin primes.
2

%I #15 Sep 08 2022 08:45:30

%S 3,7,31,37,97,157,211,331,547,577,661,727,811,937,967,1171,1297,1627,

%T 2011,2131,2137,2467,2551,2617,3067,3181,3331,3391,3607,4111,4507,

%U 4621,4861,5167,5431,5581,5851,6037,6121,6271,6841,6967,7297,7681,7867,8317

%N Primes p such that 2p - 3 and 2p - 1 are twin primes.

%H Amiram Eldar, <a href="/A128436/b128436.txt">Table of n, a(n) for n = 1..10000</a>

%t Select[Prime[Range[1000]], PrimeQ[2# - 1] && PrimeQ[2# - 3] &] (* _Ray Chandler_, May 11 2007 *)

%o (Magma) [ p: p in PrimesUpTo(9000) | IsPrime(2*p-3) and IsPrime(2*p-1)] // _Vincenzo Librandi_, Jan 29 2011

%Y Cf. A001097, A005382.

%K nonn

%O 1,1

%A _Zak Seidov_, Mar 03 2007