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A050413 Numbers n such that 74*2^n-1 is prime. 2
0, 2552, 4892, 7896, 14352, 32124, 51476 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

REFERENCES

Computed by Joe K. Crump (joecr(AT)carolina.rr.com) and (mostly) by David Broadhurst.

LINKS

Table of n, a(n) for n=1..7.

Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for k < 300

Wilfrid Keller, List of primes k.2^n - 1 for k < 300

Index entries for sequences of n such that k*2^n-1 (or k*2^n+1) is prime

PROG

(PARI) is(n)=ispseudoprime(74*2^n-1) \\ Charles R Greathouse IV, May 22 2017

CROSSREFS

Cf. A050412, A050544.

Sequence in context: A250686 A035876 A072435 * A050544 A185516 A235085

Adjacent sequences:  A050410 A050411 A050412 * A050414 A050415 A050416

KEYWORD

nonn,hard

AUTHOR

David Broadhurst, Dec 22 1999

EXTENSIONS

David Broadhurst, Dec 26 1999 reports that primality up to n=51476 is now proved, using Yves Gallot's proth.exe.

STATUS

approved

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Last modified October 20 11:14 EDT 2018. Contains 316379 sequences. (Running on oeis4.)