The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A103082 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A103082

Numbers n such that 8*10^n + 4*R_n + 5 is prime, where R_n = 11...1 is the repunit (A002275) of length n.
(history; published version)

#19 by Charles R Greathouse IV at Thu Jan 17 13:44:07 EST 2019

LINKS

Makoto Kamada, <a href="httphttps://stdkmd.comnet/nrr/8/84449.htm#prime">Prime numbers of the form 844...449</a>.

Discussion

Thu Jan 17

13:44

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

#18 by Bruno Berselli at Mon Oct 19 04:05:39 EDT 2015

STATUS

reviewed

approved

#17 by Joerg Arndt at Mon Oct 19 03:41:12 EDT 2015

STATUS

proposed

reviewed

#16 by Altug Alkan at Mon Oct 19 03:39:39 EDT 2015

STATUS

editing

proposed

#15 by Altug Alkan at Mon Oct 19 03:39:28 EDT 2015

PROG

(PARI) for(n=0, 1e5, if(isprime(k=(76*10^n+41)/9), print1(n", "))) \\ Altug Alkan, Oct 19 2015

STATUS

reviewed

editing

#14 by Joerg Arndt at Mon Oct 19 02:48:51 EDT 2015

STATUS

proposed

reviewed

#13 by Robert Price at Sun Oct 18 21:28:01 EDT 2015

STATUS

editing

proposed

#12 by Robert Price at Sun Oct 18 21:27:50 EDT 2015

COMMENTS

a(13) > 10^5. - Robert Price, Oct 18 2015

#11 by Robert Price at Sun Oct 18 21:27:17 EDT 2015

DATA

0, 1, 4, 13, 37, 46, 106, 139, 469, 5695, 56281, 58669

OFFSET

1,23

#10 by Robert Price at Sun Oct 18 21:27:06 EDT 2015

DATA

1, 4, 13, 37, 46, 106, 139, 469, 5695, 56281, 58669

FORMULA

a(n) = A101069(n-1) + 1 for n>1.

EXTENSIONS

Inserted a(1)=0 and added a(11)-a(12) by Robert Price, Oct 18 2015

STATUS

approved

editing