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Primes p of the form 6k+1 such that 6p+1 is also prime.
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%I #9 Sep 08 2022 08:45:50

%S 7,13,37,61,73,103,151,181,241,271,277,283,313,331,367,373,397,577,

%T 601,607,661,727,751,787,853,907,937,1033,1063,1117,1171,1201,1321,

%U 1327,1381,1423,1453,1531,1567,1693,1777,1831,1873,1987,1993,2137,2161,2203,2221,2281,2287,2293,2347,2551,2593,2677,2767,2791,2851,2971,3037,3061,3163,3181,3307,3391

%N Primes p of the form 6k+1 such that 6p+1 is also prime.

%t sp1Q[n_]:=IntegerQ[(n-1)/6]&&PrimeQ[6n+1]; Select[Prime[Range[500]],sp1Q] (* _Harvey P. Dale_, Apr 08 2018 *)

%o (Magma) [ p: n in [0..600] | IsPrime(6*p+1) and IsPrime(p) where p is 6*n+1 ];

%Y Subsequence of A007693 which in turn is subsequence of A024899.

%K nonn

%O 1,1

%A _Zak Seidov_, Nov 22 2010