login
The OEIS is supported by
the many generous donors to the OEIS Foundation
.
Hints
(Greetings from
The On-Line Encyclopedia of Integer Sequences
!)
A243397
Numbers n such that 19^n+4 is prime.
2
0, 1, 3, 21, 145, 273, 1425, 9613, 15711, 18445
(
list
;
graph
;
refs
;
listen
;
history
;
text
;
internal format
)
OFFSET
1,3
COMMENTS
No further terms up to 20000. -
Felix Fröhlich
, Oct 29 2014
No further terms up to 24000. -
Felix Fröhlich
, Jan 22 2015
LINKS
Table of n, a(n) for n=1..10.
MATHEMATICA
Select[Range[0, 10000], PrimeQ[19^# + 4] &] (*
Vincenzo Librandi
, Oct 16 2014 *)
PROG
(PARI) for(n=0, 10^5, if(ispseudoprime(19^n+4), print1(n, ", ")))
(Magma) [n: n in [0..1000] | IsPrime(19^n+4)]; //
Vincenzo Librandi
, Oct 16 2014
CROSSREFS
Corresponding sequences for k^n+4:
A058958
(k=3),
A124621
(k=5),
A096305
(k=7),
A217384
(k=9),
A137236
(k=13).
Sequence in context:
A228115
A033888
A141492
*
A173350
A323203
A372943
Adjacent sequences:
A243394
A243395
A243396
*
A243398
A243399
A243400
KEYWORD
nonn
,
more
AUTHOR
Felix Fröhlich
, Jun 04 2014
EXTENSIONS
a(1)-a(2) prepended by
N. J. A. Sloane
, Jun 18 2014
a(9)-a(10) from
Felix Fröhlich
, Oct 16 2014
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 12 10:37 EDT 2024. Contains 375092 sequences. (Running on oeis4.)