login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A096819 Exponents n such that 2^n-19 is prime. 11
5, 7, 11, 15, 19, 21, 31, 39, 67, 69, 85, 157, 171, 191, 255, 291, 379, 3669, 4551, 9531, 13119, 14211, 20647, 233965, 337267 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

All terms are odd since for even n, 2^n-19 is divisible by 3.

LINKS

Table of n, a(n) for n=1..25.

Search for 2^n-19, PRP Top Records

EXAMPLE

n=7: 128-19=109 is prime.

MATHEMATICA

Select[Range[5, 20000], PrimeQ[2^#-19]&] (* Vladimir Joseph Stephan Orlovsky, Feb 27 2011*)

CROSSREFS

Exponents for primes of 2^n-d form: A000043 (d=1), A050414 (d=3), A059608 (d=5), A059609 (d=7), A059610 (d=9), A096817 (d=11), A096818 (d=13), A059612 (d=15), A059611 (d=17), A096819 (d=19), A096820 (d=21).

Cf. A096502

Sequence in context: A134643 A039001 A023741 * A032699 A073088 A054059

Adjacent sequences:  A096816 A096817 A096818 * A096820 A096821 A096822

KEYWORD

nonn,more

AUTHOR

Labos Elemer, Jul 13 2004

EXTENSIONS

a(22)-a(23) from Max Alekseyev, a(24)-a(25) from Lelio R Paula, added by Max Alekseyev, Feb 10 2012, Oct 24 2013

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.

License Agreements, Terms of Use, Privacy Policy. .

Last modified September 24 16:48 EDT 2021. Contains 347651 sequences. (Running on oeis4.)