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%I #14 Jun 26 2017 13:18:10
%S 7,17,97,241,337,577,3361,3697,6961,10657,23761,25537,32257,37537,
%T 49297,64081,65521,77617,79201,89041,126001,138337,153457,171697,
%U 193441,249217,269377,287281,334561,351121,374977,474337,633937,652081,665857
%N Primes of the form 2*p^2 - 1, where p is prime.
%H T. D. Noe, <a href="/A092057/b092057.txt">Table of n, a(n) for n = 1..1000</a>
%t lst={};Do[p=Prime[n];If[PrimeQ[r=2*p^2-1],AppendTo[lst,r]],{n,6!}];lst (* _Vladimir Joseph Stephan Orlovsky_, Jun 20 2009 *)
%t Select[2#^2-1&/@Prime[Range[200]],PrimeQ] (* _Harvey P. Dale_, Jun 26 2017 *)
%o (PARI) for (i=1,300,if(isprime(2*prime(i)^2-1),print1(2*prime(i)^2-1,",")))
%Y Cf. A092058.
%Y Cf. A106483 (primes p such that 2p^2 - 1 is also prime).
%K easy,nonn
%O 1,1
%A Mohammed Bouayoun (mohammed.bouayoun(AT)sanef.com), Feb 19 2004
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