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

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 56th year, we are closing in on 350,000 sequences, and we’ve crossed 9,700 citations (which often say “discovered thanks to the OEIS”).

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A032423 Numbers k such that 147*2^k+1 is prime. 1
8, 11, 15, 18, 19, 26, 44, 60, 84, 90, 91, 134, 155, 179, 258, 275, 475, 620, 824, 888, 1731, 2194, 2328, 2568, 2915, 3554, 4319, 5340, 8054, 10088, 21660, 41851, 50535, 77719, 81660, 169658, 179034, 190911, 208731, 218300, 359710, 394394, 509831, 534558 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Jeppe Stig Nielsen, Table of n, a(n) for n = 1..52

Ray Ballinger, Proth Search Page

Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for k < 300

Y. Gallot, Proth.exe: Windows Program for Finding Large Primes

Wilfrid Keller, List of primes k.2^n - 1 for k < 300

Index entries for sequences of n such that k*2^n-1 (or k*2^n+1) is prime

MAPLE

select(k->isprime(147*2^k+1), [$0..1000])[]; # Muniru A Asiru, Dec 18 2018

MATHEMATICA

Select[Range[1000], PrimeQ[147*2^# + 1] & ] (* Robert Price, Dec 18 2018 *)

PROG

(PARI) is(n)=ispseudoprime(147*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A188199 A078117 A256073 * A063724 A317770 A154685

Adjacent sequences:  A032420 A032421 A032422 * A032424 A032425 A032426

KEYWORD

nonn

AUTHOR

James R. Buddenhagen

EXTENSIONS

a(36)-a(49) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 18 2018

Terms moved from Data section to b-file, and more terms appended to b-file, by Jeppe Stig Nielsen, Jan 19 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 | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 7 20:40 EST 2021. Contains 349589 sequences. (Running on oeis4.)