The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A032359 Numbers k such that 19*2^k+1 is prime. 2
6, 10, 46, 366, 1246, 2038, 4386, 4438, 6838, 7498, 7998, 9450, 11890, 17034, 23290, 73338, 149146, 323638, 853546, 2206266, 6833086 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Ray Ballinger, Proth Search Page
Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for k < 300
PROG
(PARI) is(n)=ispseudoprime(19*2^n+1) \\ Charles R Greathouse IV, Jun 06 2017
CROSSREFS
Sequence in context: A153328 A068588 A083333 * A346501 A115917 A275004
KEYWORD
nonn,hard
AUTHOR
EXTENSIONS
Added more terms (from http://www.prothsearch.com/riesel1.html), Joerg Arndt, Apr 07 2013
a(21) from Jeppe Stig Nielsen, Oct 30 2020
STATUS
approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 26 13:25 EDT 2024. Contains 372826 sequences. (Running on oeis4.)