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!)
A046845 Numbers n such that n*2^n+(n+1) is prime. 1
2, 38, 426, 978, 1530, 5268, 7238, 8384, 9696, 11930, 16164, 40502 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
a(6) (if it exists) > 4000. - Hiroaki Yamanouchi, Sep 22 2014
a(13) > 200000. - Giovanni Resta, May 01 2016
LINKS
MATHEMATICA
Select[Range[10^4], PrimeQ[#*2^# + (# + 1)] &] (* Michael De Vlieger, Mar 02 2015 *)
PROG
(PARI) for(n=1, 10^6, if(ispseudoprime(n*2^n+(n+1)), print1(n, ", "))); \\ Joerg Arndt, Mar 02 2015
CROSSREFS
Cf. A046844 (corresponding primes).
Sequence in context: A179503 A126731 A216357 * A098772 A207320 A262585
KEYWORD
hard,more,nonn
AUTHOR
EXTENSIONS
a(4)-a(5) from Hiroaki Yamanouchi, Sep 22 2014
New name from Hiroaki Yamanouchi, Sep 22 2014
Term a(6)-a(10) (pseudoprimes) from Joerg Arndt, Mar 02 2015
a(11)-a(12) (pseudoprimes) from Giovanni Resta, May 01 2016
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 19 04:51 EDT 2024. Contains 374388 sequences. (Running on oeis4.)