The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A273728 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A273728

Numbers k such that (17*10^k + 79)/3 is prime.
(history; published version)

#22 by Alois P. Heinz at Sun May 26 14:58:41 EDT 2024

STATUS

proposed

approved

#21 by Jon E. Schoenfield at Sun May 26 14:24:46 EDT 2024

STATUS

editing

proposed

#20 by Jon E. Schoenfield at Sun May 26 14:23:54 EDT 2024

COMMENTS

For k > 1, numbers k such that the digit 5 followed by k-2 occurrences of the digit 6 followed by the digits 93 is prime (see Example section).

LINKS

Makoto Kamada, <a href="https://stdkmd.net/nrr/prime/primedifficultyprime_difficulty.txt">Search for 56w93</a>.

EXAMPLE

Initial terms and primes associated primes:

STATUS

approved

editing

#19 by Alois P. Heinz at Mon Jul 10 10:07:21 EDT 2023

STATUS

editing

approved

#18 by Alois P. Heinz at Mon Jul 10 10:07:18 EDT 2023

COMMENTS

a(30) > 3*10^5. - _Robert Price_, Jul 10 2023

STATUS

reviewed

editing

#17 by Michel Marcus at Mon Jul 10 09:44:57 EDT 2023

STATUS

proposed

reviewed

#16 by Robert Price at Mon Jul 10 09:43:06 EDT 2023

STATUS

editing

proposed

#15 by Robert Price at Mon Jul 10 09:43:01 EDT 2023

COMMENTS

a(30) > 23*10^5.

STATUS

approved

editing

#14 by Alois P. Heinz at Mon Apr 15 16:26:38 EDT 2019

STATUS

proposed

approved

#13 by Alois P. Heinz at Mon Apr 15 13:46:27 EDT 2019

STATUS

editing

proposed

Discussion

Mon Apr 15

15:05

Felix Fröhlich: hard?