A090609 Primes of the form 6*p - 1 such that p and 6*p - 5 are primes.
11, 17, 41, 101, 113, 281, 317, 353, 401, 617, 677, 761, 941, 1433, 1613, 1697, 1877, 2273, 2297, 2381, 2693, 2801, 3461, 3677, 3701, 3881, 4937, 4973, 5441, 5573, 5861, 6581, 6737, 7673, 8237, 8681, 8933, 9137, 10181, 10337, 10733, 11261, 11597, 12101
Offset: 1
Programs
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Mathematica
Select[6Prime[Range[300]]-1,PrimeQ[#]&&PrimeQ[#-4]&] (* Stefano Spezia, Feb 12 2025 *)
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PARI
lista(nn) = forprime(p=2, nn, if(isprime(6*p-1)&&isprime(6*p-5), print1(6*p-1, ", "))); \\ Jinyuan Wang, Aug 04 2021
Formula
a(n) = 6*A089144(n) - 1.
Extensions
Name clarified and offset changed to 1 by Jinyuan Wang, Aug 03 2021