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Greater of twin primes p such that 3*p-2 is also greater of twin primes.
3

%I #18 Sep 08 2022 08:45:53

%S 5,7,61,271,1951,3001,6361,11491,11551,14551,18541,19891,21841,31081,

%T 32911,32971,33331,33601,42571,42841,50461,53551,58111,68881,70201,

%U 74611,79231,80911,93811,96331,98911,104311,109141,114601,121021,125791

%N Greater of twin primes p such that 3*p-2 is also greater of twin primes.

%H Amiram Eldar, <a href="/A177336/b177336.txt">Table of n, a(n) for n = 1..10000</a>

%F From _Wesley Ivan Hurt_, May 03 2022: (Start)

%F a(n) = A132929(n) + 1.

%F a(n) = A174920(n) + 2. (End)

%e a(1) = 5 because 5 is the greater of the twin primes (3, 5) and 3*5 - 2 = 13 is the greater of the twin primes (11, 13).

%t Select[Range[3, 126000], And @@ PrimeQ[{#, # - 2, 3# - 2, 3# - 4}] &] (* _Amiram Eldar_, Dec 23 2019 *)

%o (Magma) [p:p in PrimesInInterval(3,130000)| IsPrime(p-2) and IsPrime(3*p-2) and IsPrime(3*p-4)]; // _Marius A. Burtea_, Dec 23 2019

%Y Cf. A006512, A038869, A088878.

%Y Cf. A132929, A174920.

%K nonn

%O 1,1

%A _Juri-Stepan Gerasimov_, May 07 2010

%E Definition corrected, 1231 and 1483 inserted, and all values above 3000 corrected by _R. J. Mathar_, May 10 2010

%E Terms corrected to match definition by _D. S. McNeil_, May 10 2010

%E Name corrected by _Amiram Eldar_, Dec 23 2019