This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A063799 Numbers k such that (k+3, k+5, k+17, k+257, k+65537) are all primes. 2
 14, 26, 176, 806, 1604, 1994, 2264, 3254, 3326, 4226, 4646, 9716, 9854, 11486, 13994, 15644, 15884, 17186, 19424, 21584, 22274, 23054, 25166, 25304, 26696, 30386, 34124, 34256, 36524, 37304, 42176, 43784, 49664, 53144, 56906, 58436 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS 3, 5, 17 and 65537 are the known Fermat primes (see A019434). The counting function p(N) seems to follows the law: p(N)~c*N^(gamma) where c is a positive constant and gamma the Euler function. If so the sequence should be infinite. LINKS Harry J. Smith, Table of n, a(n) for n = 1..1000 EXAMPLE a(1)=14 because 14+3 = 17, 14+5 = 19, 14+17 = 31, 14+257 = 271, 14+65537 = 65551 are all primes. PROG (PARI) { n=0; for (m=1, 10^9, if(isprime(m + 3) && isprime(m + 5) && isprime(m + 17) && isprime(m + 257) && isprime(m + 65537), write("b063799.txt", n++, " ", m); if (n==1000, break)) ) } \\ Harry J. Smith, Aug 31 2009 CROSSREFS Cf. A019434. Sequence in context: A112772 A155505 A086258 * A086451 A190991 A306985 Adjacent sequences:  A063796 A063797 A063798 * A063800 A063801 A063802 KEYWORD easy,nonn AUTHOR Felice Russo, Aug 20 2001 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified May 25 22:17 EDT 2019. Contains 323576 sequences. (Running on oeis4.)