login
A123195
Numbers n such that A065507[n] = n.
0
OFFSET
1,1
COMMENTS
A065507[n] is the smallest prime q such that (p^q+1)/(p+1) is a prime, where p = Prime(n).
EXAMPLE
A065507[n] begins {3, 3, 5, 3, 5, 3, 7, 17, 11, 7, 109, 5, 17, 5, 5, 21943, 17,...}.
Thus
a(1) = 5 because A065507[5] = 5,
a(2) = 7 because A065507[7] = 7,
a(3) = 17 because A065507[17] = 17.
CROSSREFS
Cf. A065507.
Sequence in context: A079604 A101580 A190663 * A248480 A243844 A271656
KEYWORD
hard,more,nonn
AUTHOR
Alexander Adamchuk, Oct 04 2006
STATUS
approved