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%I #41 Sep 17 2024 15:44:31
%S 2,3,7,11,13,17,41,43,59,73,109,113,127,137,157,179,181,197,199,211,
%T 251,263,277,293,311,353,367,379,409,419,433,487,563,571,577,617,619,
%U 659,701,739,743,757,797,811,827,829,839,857,937,941,1009,1039,1063
%N Primes p such that 2*p^2 - 1 is also prime.
%H Alois P. Heinz, <a href="/A106483/b106483.txt">Table of n, a(n) for n = 1..10000</a> (first 1000 terms from T. D. Noe)
%F a(n) is in this sequence iff A007588(a(n)) is an element of A001358.
%F a(n) is in this sequence iff A106482(a(n)) = 2.
%F a(n) is in this sequence iff a(n) is prime and 2*a(n)^2-1 is also prime.
%F a(n) = prime(A092058(n)). - _R. J. Mathar_, Aug 20 2019
%p q:= p-> andmap(isprime, [p, 2*p^2-1]):
%p select(q, [$2..2000])[]; # _Alois P. Heinz_, Jun 21 2022
%t Select[Table[Prime[n], {n, 500}], PrimeQ[2*#^2 - 1] &] (* _Ray Chandler_, May 03 2005 *)
%o (Magma) [p: p in PrimesUpTo(2500)| IsPrime(2*p^2-1)]; // _Vincenzo Librandi_, Jan 29 2011
%Y Cf. A000040, A001358, A007588, A106482, A106484, A177104 (2p^3-1 prime), A182785 (2p^4-1 prime)
%Y Cf. A092057 (2p^2 - 1).
%K easy,nonn
%O 1,1
%A _Jonathan Vos Post_, May 03 2005
%E Extended by _Ray Chandler_, May 03 2005