The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A245743 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A245743

Primes p such that p - d is also prime, where d is the largest digit of p.
(history; published version)

#18 by Charles R Greathouse IV at Thu Sep 08 08:46:09 EDT 2022

PROG

(MAGMAMagma) [p: p in PrimesUpTo(7000) | IsPrime(p-d) where d is Max(Intseq(p))]; // Bruno Berselli, Jul 31 2014

Discussion

Thu Sep 08

08:46

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

#17 by Alois P. Heinz at Sun Aug 03 18:23:39 EDT 2014

STATUS

proposed

approved

#16 by Robert Israel at Sun Aug 03 18:20:28 EDT 2014

STATUS

editing

proposed

#15 by Robert Israel at Sun Aug 03 18:20:20 EDT 2014

COMMENTS

The largest digit of a(n) is 2, 4, 6 or 8. - Robert Israel, Aug 03 2014

MAPLE

filter:= n -> isprime(n) and isprime(n - max(convert(n, base, 10))):

select(filter, [$1..10^5]); # Robert Israel, Aug 03 2014

STATUS

proposed

editing

#14 by Colin Barker at Sun Aug 03 14:36:39 EDT 2014

STATUS

editing

proposed

#13 by Colin Barker at Sun Aug 03 14:36:28 EDT 2014

COMMENTS

The rightmost least significant digit of a(n) is either 1, 3 or 7. - _Colin Barker_, Aug 03 2014

#12 by Alonso del Arte at Sun Aug 03 14:14:24 EDT 2014

STATUS

proposed

editing

#11 by Colin Barker at Sun Aug 03 12:51:36 EDT 2014

STATUS

editing

proposed

Discussion

Sun Aug 03

14:14

Alonso del Arte: Sign that comment.

#10 by Colin Barker at Sun Aug 03 12:51:10 EDT 2014

COMMENTS

The rightmost digit of a(n) is either 1, 3 or 7.

STATUS

approved

editing

Discussion

Sun Aug 03

12:51

Colin Barker: Added a comment.

#9 by Bruno Berselli at Fri Aug 01 06:03:22 EDT 2014

STATUS

proposed

approved