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A169716 Numbers n such that 2^n-127 is prime. 2
47, 55, 103, 143, 391, 2807, 11647, 19223 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Exponents n arising in A175347: see that sequence for the actual primes.

The next term is > 10^4. [M. F. Hasler, Apr 18 2010]

All terms are == 7 (mod 8). [Hasler]

No more terms through 78815. - Charles R Greathouse IV, Apr 19 2010

LINKS

Table of n, a(n) for n=1..8.

Charles R Greathouse IV, Re: A175347: Primes in A176303, seqfan list, Apr 19 2010.

PROG

(PARI) is(n)=ispseudoprime(2^n-127) \\ Charles R Greathouse IV, Sep 14 2015

CROSSREFS

Cf. A175347, A176303.

Sequence in context: A106279 A275022 A048581 * A045140 A104852 A061758

Adjacent sequences:  A169713 A169714 A169715 * A169717 A169718 A169719

KEYWORD

nonn

AUTHOR

Zak Seidov, Apr 18 2010

EXTENSIONS

More terms from M. F. Hasler, Apr 18 2010

a(7), a(8) from Charles R Greathouse IV, Apr 19 2010

STATUS

approved

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Last modified November 22 05:36 EST 2017. Contains 295076 sequences.