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!)
A300408 Primes of the form 19*2^n + 1. 3
1217, 19457, 1337006139375617 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Next term a(4) = 19*2^366 + 1 > 10^111.
For the corresponding exponents n see A032359.
LINKS
Ray Ballinger, Wilfried Keller, List of primes k*2^n + 1 for k < 300.
MAPLE
a:=(n, k)->`if`(isprime(k*2^n+1), k*2^n+1, NULL):
seq(a(n, 19), n=1..366);
PROG
(GAP) Filtered(List([1..500], n->19*2^n + 1), IsPrime); # Muniru A Asiru, Mar 06 2018
(PARI) lista(nn) = {for(k=1, nn, if(ispseudoprime(p=19*2^k+1), print1(p, ", "))); } \\ Altug Alkan, Mar 29 2018
CROSSREFS
Sequence in context: A059669 A032628 A175964 * A252600 A293479 A031781
KEYWORD
nonn,less
AUTHOR
Martin Renner, Mar 05 2018
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 July 18 16:59 EDT 2024. Contains 374388 sequences. (Running on oeis4.)