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 A108258 Consider primes p and q such that p = 3^k + 20 and q = 3^(k+1) + 20 for some k; sequence gives values of q. 1
 29, 47, 101, 263, 6581, 177167 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE 3^1 + 20 = 23, 3^2 + 20 = 29. MATHEMATICA Transpose[Select[Partition[#+20&/@(3^Range), 2, 1], AllTrue[ #, PrimeQ]&]] [] (* The program uses the function AllTrue from Mathematica version 10 *) (* Harvey P. Dale, Oct 29 2014 *) PROG (PARI) g(m, n, b) = { for(x=0, n, y=m+b^x+b%2; z=m+b^(x+1)+b%2; if(isprime(y)&isprime(z), print1(z", ") ) ) } CROSSREFS Cf. A108249. Sequence in context: A106754 A222413 A063642 * A232236 A228585 A042947 Adjacent sequences:  A108255 A108256 A108257 * A108259 A108260 A108261 KEYWORD nonn AUTHOR Cino Hilliard, Jun 29 2005 STATUS approved

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Last modified May 22 21:50 EDT 2019. Contains 323504 sequences. (Running on oeis4.)