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 A066179 Primes p such that (p-1)/2 and (p-3)/4 are also prime. 10
 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; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS 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. LINKS Harry J. Smith, Table of n, a(n) for n=1,...,1000 MATHEMATICA lst={}; Do[p=Prime[n]; If[PrimeQ[a=(p-1)/2]&&PrimeQ[(a-1)/2], AppendTo[lst, p]], {n, 8!}]; lst (* Vladimir Joseph Stephan Orlovsky, Feb 27 2009 *) PROG (PARI) { n=0; default(primelimit, 4294965247); for (m=1, 10^9, p=prime(m); if (frac((p-3)/4), next); if (isprime((p-3)/4) && isprime((p-1)/2), write("b066179.txt", n++, " ", p); if (n==1000, return)) ) } \\ Harry J. Smith, Feb 05 2010 CROSSREFS Sequence in context: A100558 A126199 A096342 * A217566 A278869 A272628 Adjacent sequences:  A066176 A066177 A066178 * A066180 A066181 A066182 KEYWORD nonn AUTHOR Vladeta Jovovic, Dec 14 2001 EXTENSIONS Offset changed from 0 to 1 by Harry J. Smith, Feb 05 2010 STATUS approved

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Last modified June 4 17:50 EDT 2020. Contains 334828 sequences. (Running on oeis4.)