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%I #17 Jan 02 2023 12:30:47
%S 47,55,103,143,391,2807,11647,19223
%N Numbers n such that 2^n-127 is prime.
%C Exponents n arising in A175347: see that sequence for the actual primes.
%C The next term is > 10^4. [M. F. Hasler, Apr 18 2010]
%C All terms are == 7 (mod 8). [Hasler]
%C No more terms through 78815. - _Charles R Greathouse IV_, Apr 19 2010
%H Charles R Greathouse IV, <a href="http://list.seqfan.eu/oldermail/seqfan/2010-April/004363.html">Re: A175347: Primes in A176303</a>, seqfan list, Apr 19 2010.
%o (PARI) is(n)=ispseudoprime(2^n-127) \\ _Charles R Greathouse IV_, Sep 14 2015
%Y Cf. A175347, A176303.
%K nonn
%O 1,1
%A _Zak Seidov_, Apr 18 2010
%E More terms from _M. F. Hasler_, Apr 18 2010
%E a(7), a(8) from _Charles R Greathouse IV_, Apr 19 2010
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