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A066179 n, (n-1)/2, (n-3)/4 all prime. +0
8
11, 23, 47, 167, 359, 719, 1439, 2039, 2879, 4079, 4127, 4919, 5639, 5807, 5927, 6047, 7247, 7559, 7607, 7727, 9839, 10799, 11279, 13799, 13967, 14159, 15287, 15647, 20327, 21599, 21767, 23399, 24407, 24527, 25799, 28319, 28607, 29399 (list; graph; listen)
OFFSET

0,1

COMMENT

Call p m-prime iff (p-(2^i-1))/2^i is prime for i=0 .. m; sequence gives 2-primes. 0-primes are primes (A000040) and 1-primes are safe primes (A005385). a(n)-1 and a(n) are consecutive terms of the sequence A065966. It is not known if there are infinitely many m-primes for m > 0.

MATHEMATICA

lst={}; Do[p=Prime[n]; If[PrimeQ[a=(p-1)/2]&&PrimeQ[(a-1)/2], AppendTo[lst, p]], {n, 8!}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Feb 27 2009]

CROSSREFS

Sequence in context: A100558 A126199 A096342 this_sequence A141093 A041236 A097485

Adjacent sequences: A066176 A066177 A066178 this_sequence A066180 A066181 A066182

KEYWORD

nonn

AUTHOR

Vladeta Jovovic (vladeta(AT)eunet.rs), Dec 14 2001

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Last modified November 25 20:09 EST 2009. Contains 167514 sequences.


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