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 A160027 Primes of the form 2^(2^k)+15. 8
 17, 19, 31, 271, 65551, 4294967311 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Fermat primes of order 15. The number of Fermat primes of order 15 exceeds the number of known Fermat primes. Terms given correspond to n= 0, 1, 2, 3, 4 and 5. Next term >= 2^2^16 + 15. - Vincenzo Librandi, Jun 07 2016 Next term >= 2^2^17 + 15. - Charles R Greathouse IV, Jun 07 2016 LINKS FORMULA Intersection of the primes and the set of Fermat numbers F(k,m) = 2^(2^k)+m of order m=15. EXAMPLE For k = 5, 2^32 + 15 = 4294967311 is prime. MATHEMATICA Select[Table[2^(2^n) + 15, {n, 0, 10}], PrimeQ] (* Vincenzo Librandi, Jun 07 2016 *) PROG (PARI) g(n, m) = for(x=0, n, y=2^(2^x)+m; if(ispseudoprime(y), print1(y", "))) (MAGMA) [a: n in [0..15] | IsPrime(a) where a is 2^(2^n)+15]; // Vincenzo Librandi, Jun 07 2016 CROSSREFS Cf. A019434 (order 1), A104067 (superset for order 13), A160028 (order 81). Cf. similar sequences listed in A273547. Sequence in context: A292237 A085106 A079592 * A288407 A286611 A144213 Adjacent sequences:  A160024 A160025 A160026 * A160028 A160029 A160030 KEYWORD nonn AUTHOR Cino Hilliard, Apr 30 2009 EXTENSIONS Edited by R. J. Mathar, May 08 2009 STATUS approved

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Last modified November 20 20:46 EST 2019. Contains 329347 sequences. (Running on oeis4.)