The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A124515

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A124515

Numbers k for which 2*k-1, 4*k-1, 8*k-1, 16*k-1, 32*k-1, 64*k-1, 128*k-1 and 256*k-1 are primes.
(history; published version)

#12 by Michel Marcus at Fri Mar 27 09:02:08 EDT 2020

STATUS

reviewed

approved

#11 by Joerg Arndt at Fri Mar 27 08:57:41 EDT 2020

STATUS

proposed

reviewed

#10 by Amiram Eldar at Fri Mar 27 08:03:23 EDT 2020

STATUS

editing

proposed

#9 by Amiram Eldar at Fri Mar 27 07:41:11 EDT 2020

NAME

Numbers n k for which 2n2*k-1, 4n4*k-1, 8n8*k-1, 16n16*k-1, 32n32*k-1, 64n64*k-1, 128n128*k-1 and 256n256*k-1 are primes.

#8 by Amiram Eldar at Fri Mar 27 07:40:43 EDT 2020

LINKS

Amiram Eldar, <a href="/A124515/b124515.txt">Table of n, a(n) for n = 1..1000</a>

STATUS

approved

editing

#7 by Ray Chandler at Fri Oct 11 11:04:07 EDT 2019

STATUS

editing

approved

#6 by Ray Chandler at Fri Oct 11 11:04:04 EDT 2019

MATHEMATICA

Select[15*Range[76000000], And @@ PrimeQ /@ ({2, 4, 8, 16, 32, 64, 128, 256}*# - 1) &] (* _Ray Chandler_, Nov 22 2006 *)

STATUS

approved

editing

#5 by Russ Cox at Sat Mar 31 10:22:00 EDT 2012

AUTHOR

_Artur Jasinski (grafix(AT)csl.pl), _, Nov 04 2006

Discussion

Sat Mar 31

10:22

OEIS Server: https://oeis.org/edit/global/339

#4 by Russ Cox at Fri Mar 30 17:29:53 EDT 2012

EXTENSIONS

Extended by _Ray Chandler (rayjchandler(AT)sbcglobal.net), _, Nov 22 2006

Discussion

Fri Mar 30

17:29

OEIS Server: https://oeis.org/edit/global/154

#3 by N. J. A. Sloane at Sun Jun 29 03:00:00 EDT 2008

MATHEMATICA

Select[15*Range[76000000], And @@ PrimeQ /@ ({2, 4, 8, 16, 32, 64, 128, 256}*# - 1) &] (*Chandler*)

KEYWORD

nonn,new

nonn