login
The OEIS is supported by
the many generous donors to the OEIS Foundation
.
Hints
(Greetings from
The On-Line Encyclopedia of Integer Sequences
!)
A093169
Primes of the form 50*R_k + 7, where R_k is the repunit (
A002275
) of length k.
1
7, 557, 5557, 555557, 5555555557, 555555555555557, 5555555555555555555557, 5555555555555555555555555555555555555555555555555555555555555555555555555555555555555557
(
list
;
graph
;
refs
;
listen
;
history
;
text
;
internal format
)
OFFSET
1,1
COMMENTS
Primes of the form (5*10^k + 13)/9. -
Vincenzo Librandi
, Nov 16 2010
LINKS
Table of n, a(n) for n=1..8.
Makoto Kamada,
Prime numbers of the form 55...557
.
Index entries for primes involving repunits
CROSSREFS
Cf.
A056686
(corresponding k).
Sequence in context:
A182433
A329368
A333208
*
A159029
A308582
A332157
Adjacent sequences:
A093166
A093167
A093168
*
A093170
A093171
A093172
KEYWORD
nonn
AUTHOR
Rick L. Shepherd
, Mar 26 2004
STATUS
approved
Lookup
|
Welcome
|
Wiki
|
Register
|
Music
|
Plot 2
|
Demos
|
Index
|
Browse
|
More
|
WebCam
Contribute new seq. or comment
|
Format
|
Style Sheet
|
Transforms
|
Superseeker
|
Recents
The OEIS Community
| Maintained by
The OEIS Foundation Inc.
License Agreements, Terms of Use, Privacy Policy.
.
Last modified August 5 10:59 EDT 2024. Contains 374950 sequences. (Running on oeis4.)