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%I #21 Jan 27 2021 16:08:52
%S 7,10,16,34,70,88,124,160,250,268,340,394,520,538,574,700,718,754,844,
%T 880,1078,1258,1294,1330,1474,1528,1780,1924,1960,1978,2050,2158,2230,
%U 2284,2428,2734,2860,3040,3058,3094,3148,3310,3670,3688,3868,4228,4318
%N Sum of Sophie Germain prime p and corresponding safe prime q=2p+1.
%C For n > 1, numbers of the form 6k-2 such that Omega( (2k-1)(4k-1) ) = 2. - _Wesley Ivan Hurt_, Jun 28 2013
%C First semiprimes: 10,34,394,538,718,1294,2734. - _Zak Seidov_, Sep 07 2016
%H N. J. A. Sloane, <a href="/A175666/b175666.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A005384(n)+A005385(n) = 3*A005384(n)+1 = (3*A005385(n)-1)/2.
%o (PARI) is(n)=n%3==1 && isprime(n\3) && isprime((2*n+1)/3) \\ _Charles R Greathouse IV_, Jun 28 2013
%Y Cf. A005384, A005385.
%K nonn
%O 1,1
%A _Zak Seidov_, Aug 05 2010
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