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A108260 Consider primes p and q such that p = 3^k + 14 and q = 3^(k+1) + 14 for some k; sequence gives values of p. 0
17, 23, 257, 19697 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

There are no additional terms up to k=2000, which generates a 955-digit nonprime candidate number for p. - Harvey P. Dale, Aug 17 2014

LINKS

Table of n, a(n) for n=0..3.

EXAMPLE

3^1 + 14 = 17, 3^2 + 14 = 23.

MATHEMATICA

Transpose[Select[Table[{3^k+14, 3^(k+1)+14}, {k, 10}], AllTrue[ #, PrimeQ]&]] [[1]] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Aug 17 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(y", ") ) ) }

CROSSREFS

Sequence in context: A127924 A250640 A344636 * A062628 A127907 A070687

Adjacent sequences:  A108257 A108258 A108259 * A108261 A108262 A108263

KEYWORD

nonn

AUTHOR

Cino Hilliard, Jun 29 2005

STATUS

approved

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Last modified August 15 08:46 EDT 2022. Contains 356135 sequences. (Running on oeis4.)