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Revision History for A091923

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

A091923

Primes whose decimal representations interpreted in base 11 are not prime.
(history; published version)

#17 by Charles R Greathouse IV at Thu Sep 08 08:45:13 EDT 2022

PROG

(MAGMAMagma) [n:n in PrimesUpTo(400)| not IsPrime(Seqint(Intseq(n), 11))]; // Marius A. Burtea, Jun 30 2019

Discussion

Thu Sep 08

08:45

OEIS Server: https://oeis.org/edit/global/2944

#16 by Joerg Arndt at Sat Jul 06 05:06:27 EDT 2019

STATUS

reviewed

approved

#15 by Amiram Eldar at Sat Jul 06 05:04:33 EDT 2019

STATUS

proposed

reviewed

#14 by Vincenzo Librandi at Mon Jul 01 00:48:48 EDT 2019

STATUS

editing

proposed

#13 by Vincenzo Librandi at Mon Jul 01 00:48:41 EDT 2019

MATHEMATICA

Select[Prime@Range@80, ! PrimeQ@FromDigits[IntegerDigits@#, 11] &] (* Vincenzo Librandi, Jul 01 2019 *)

STATUS

proposed

editing

#12 by Michel Marcus at Sun Jun 30 17:07:18 EDT 2019

STATUS

editing

proposed

Discussion

Sun Jun 30

17:08

Michel Marcus: please see A308917

#11 by Michel Marcus at Sun Jun 30 17:07:15 EDT 2019

PROG

(PARI) isok(p) = isprime(p) && (d=digits(p)) && !isprime(fromdigits(d, 11)); \\ Michel Marcus, Jun 30 2019

STATUS

proposed

editing

#10 by Marius A. Burtea at Sun Jun 30 16:33:37 EDT 2019

STATUS

editing

proposed

#9 by Marius A. Burtea at Sun Jun 30 16:33:25 EDT 2019

LINKS

Marius A. Burtea, <a href="/A091923/b091923.txt">Table of n, a(n) for n = 1..1045</a>

PROG

(MAGMA) [n:n in PrimesUpTo(400)| not IsPrime(Seqint(Intseq(n), 11))]; // Marius A. Burtea, Jun 30 2019

STATUS

approved

editing

#8 by Jon E. Schoenfield at Fri Jan 04 19:01:25 EST 2019

STATUS

editing

approved