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%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