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A175171 Primes p such that 3*2^p-1 is also prime 0
2, 3, 7, 11, 43, 103, 827, 7559, 26459, 164987 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

These are the primes in A002235. [From R. J. Mathar, May 02 2010]

LINKS

Table of n, a(n) for n=1..10.

EXAMPLE

For p=2, 3*2^2-1=11; p=3, 3*2^3-1=23; p=7, 3*2^7-1=383

PROG

(MAGMA) [p: p in PrimesUpTo(7000) | IsPrime(3*2^p-1) ]

CROSSREFS

Sequence in context: A072534 A056292 A106125 * A073609 A267091 A053781

Adjacent sequences:  A175168 A175169 A175170 * A175172 A175173 A175174

KEYWORD

nonn

AUTHOR

Vincenzo Librandi, Mar 09 2010

EXTENSIONS

3 more terms from R. J. Mathar, May 02 2010

STATUS

approved

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Last modified December 1 20:01 EST 2021. Contains 349430 sequences. (Running on oeis4.)