The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A211162 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A211162

Sophie Germain 5-almost primes.
(history; published version)

#27 by Charles R Greathouse IV at Thu Sep 08 08:46:02 EDT 2022

PROG

(MAGMAMagma) Is5primes:=func<i|&+[d[2]: d in Factorization(i)] eq 5>; [n: n in [2..22000] | Is5primes(n) and Is5primes(2*n+1)]; // Bruno Berselli, Jan 30 2013

Discussion

Thu Sep 08

08:46

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

#26 by Charles R Greathouse IV at Wed Feb 01 22:33:06 EST 2017

STATUS

editing

approved

#25 by Charles R Greathouse IV at Wed Feb 01 22:33:03 EST 2017

PROG

(PARI) is(n)=bigomega(n)==5 && bigomega(2*n+1)==5 \\ Charles R Greathouse IV, Feb 01 2017

STATUS

approved

editing

#24 by Wesley Ivan Hurt at Fri Oct 21 12:34:59 EDT 2016

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reviewed

approved

#23 by Michel Marcus at Fri Oct 21 11:16:17 EDT 2016

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proposed

reviewed

#22 by Bruno Berselli at Fri Oct 21 11:11:55 EDT 2016

STATUS

editing

proposed

#21 by Bruno Berselli at Fri Oct 21 11:11:52 EDT 2016

COMMENTS

Contribution from _From _Zak Seidov_, Jan 30 2013. : (Start)

First integers n such that n, 2n+1, 4n+3, 8n+7, 16n+15, 32n+31 and 64n+63 all are Sophie Germain 5-almost primes are: 433833417, 463078210, 648871975. (endEnd)

STATUS

approved

editing

#20 by Bruno Berselli at Fri Mar 15 06:38:35 EDT 2013

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reviewed

approved

#19 by Joerg Arndt at Thu Mar 14 05:45:51 EDT 2013

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proposed

reviewed

#18 by Vincenzo Librandi at Wed Mar 13 16:43:43 EDT 2013

STATUS

editing

proposed