|
Search: id:A117847
|
|
|
| A117847 |
|
Numbers n such that A102578(n)*p(n)#-1 is a Sophie Germain prime. |
|
+0
1
|
| |
|
|
OFFSET
|
1,1
|
|
|
COMMENT
|
This sequence gives first of twin primes which are also Sophie Germain primes
|
|
EXAMPLE
|
16*(29#)-1 is the first of twin primes, 16=A102578(10)
2*(16*(29#)-1)+1 is prime so 16*(29#)-1 is a Sophie Germain prime
|
|
CROSSREFS
|
Cf. A102578.
Sequence in context: A120138 A050200 A034961 this_sequence A057990 A091022 A133372
Adjacent sequences: A117844 A117845 A117846 this_sequence A117848 A117849 A117850
|
|
KEYWORD
|
hard,more,nonn
|
|
AUTHOR
|
Pierre CAMI (pierrecami(AT)tele2.fr), May 01 2006
|
|
|
Search completed in 0.002 seconds
|
