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First member of a prime sextuplet in a 2p-1 progression.
10

%I #20 Aug 13 2024 15:48:33

%S 16651,33301,165901,331801,385591,445741,478801,580471,1203121,

%T 1768441,1943371,2041201,2131141,2240941,2340661,2393431,2526721,

%U 3277471,3536881,3623881,3880381,3897631,4123621,4415371,4481881,5278591

%N First member of a prime sextuplet in a 2p-1 progression.

%C Numbers n such that n remains prime through 5 iterations of function f(x) = 2x - 1.

%H <a href="/index/Pri#primes_AP">Index entries for sequences related to primes in arithmetic progressions</a>

%e First sextuplet is (16651,33301,66601,133201,266401,532801).

%o (Magma) [ p: p in PrimesUpTo(6*10^6) | forall{q: k in [1..5] | IsPrime(q) where q is 2^k*(p-1)+1} ]; // _Bruno Berselli_, Nov 23 2011

%Y Cf. A005382 and A005383; A057326, A057327, A057328, A057330, A005603.

%K nonn

%O 1,1

%A _Patrick De Geest_, Aug 15 2000

%E Offset changed by _Andrew Howroyd_, Aug 13 2024