|
Search: id:A103001
|
|
|
| A103001 |
|
Numbers n such that 5*10^n - 9 is prime. |
|
+0
2
|
|
| 1, 2, 4, 7, 24, 172, 173, 218, 439, 2563, 2782, 2880, 3715, 4392, 10820, 14592
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
COMMENT
|
Also numbers n such that 4*10^n + 9*R_n - 8 is prime, where R_n = 11...1 is the repunit (A002275) of length n.
|
|
LINKS
|
Makoto Kamada, Factorizations of 499...991.
Index entries for primes involving repunits.
|
|
MATHEMATICA
|
Do[ If[ PrimeQ[5*10^n - 9], Print[n]], {n, 0, 10000}]
|
|
CROSSREFS
|
Sequence in context: A138049 A099387 A036440 this_sequence A065846 A047904 A102118
Adjacent sequences: A102998 A102999 A103000 this_sequence A103002 A103003 A103004
|
|
KEYWORD
|
more,nonn
|
|
AUTHOR
|
Robert G. Wilson v (rgwv(AT)rgwv.com), Jan 17 2005
|
|
EXTENSIONS
|
More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 01 2008
|
|
|
Search completed in 0.002 seconds
|
