The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A095714

(Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing entries 1-10 | older changes

A095714

Numbers k such that 9*R_k - 8 is prime, where R_k = 11...1 is the repunit (A002275) of length k.
(history; published version)

#35 by Joerg Arndt at Thu Jul 08 05:04:55 EDT 2021

STATUS

proposed

approved

#34 by Jon E. Schoenfield at Thu Jul 08 04:59:32 EDT 2021

STATUS

editing

proposed

#33 by Jon E. Schoenfield at Thu Jul 08 04:59:25 EDT 2021

NAME

Numbers n k such that 9*R_n k - 8 is prime, where R_n k = 11...1 is the repunit (A002275) of length nk.

COMMENTS

Also numbers n k such that 10^n k - 9 is a prime.

STATUS

approved

editing

#32 by Charles R Greathouse IV at Thu Jan 17 13:44:06 EST 2019

LINKS

Makoto Kamada, <a href="httphttps://stdkmd.comnet/nrr/9/99991.htm#prime">Prime numbers of the form 99...991</a>.

Discussion

Thu Jan 17

13:44

OEIS Server: https://oeis.org/edit/global/2791

#31 by N. J. A. Sloane at Fri Dec 15 17:36:41 EST 2017

EXTENSIONS

a(15) - a(16) from _Jason Earls (zevi_35711(AT)yahoo.com), _, Jan 07 2008

Discussion

Fri Dec 15

17:36

OEIS Server: https://oeis.org/edit/global/2722

#30 by Ray Chandler at Thu May 21 19:30:11 EDT 2015

STATUS

editing

approved

#29 by Ray Chandler at Thu May 21 19:29:51 EDT 2015

CROSSREFS

Cf. A002275, A093177, A056696.

STATUS

approved

editing

#28 by Ray Chandler at Mon Apr 27 09:01:59 EDT 2015

STATUS

editing

approved

#27 by Ray Chandler at Mon Apr 27 09:01:51 EDT 2015

LINKS

Makoto Kamada, <a href="http://homepage2.niftystdkmd.com/m_kamadanrr/math9/99991.htm#prime">Prime numbers of the form 99...991</a>.

STATUS

approved

editing

#26 by N. J. A. Sloane at Sun Sep 07 13:23:02 EDT 2014

STATUS

editing

approved