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%I #15 Sep 08 2022 08:45:55
%S 2,5,7,47,79,103,131,139,149,173,197,229,307,313,331,373,439,541,547,
%T 593,659,743,761,797,853,859,863,883,919,937,1051,1093,1097,1163,1171,
%U 1301,1303,1451,1471,1549,1601,1657,1721,1861,1973,2039,2081,2087,2099,2129,2161,2239,2269,2393,2417,2437,2473,2521
%N Primes p such that 2*p^4-1 is also prime.
%H Vincenzo Librandi, <a href="/A182785/b182785.txt">Table of n, a(n) for n = 1..1000</a>
%F A000040 INTERSECT A182783.
%t Select[Prime[Range[500]], PrimeQ[2 #^4 - 1]&] (* _Vincenzo Librandi_, Apr 17 2013 *)
%o (Magma) [p: p in PrimesUpTo(2600)| IsPrime(2*p^4 - 1)]; // _Vincenzo Librandi_, Apr 17 2013
%Y Cf. A182783, A182784, A106483 (2p^2-1 prime), A177104 (2p^3-1 prime), A309855 (2p^5-1 prime).
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Dec 02 2010
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