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A123195 Numbers n such that A065507[n] = n. 0
5, 7, 17, 59 (list; graph; refs; listen; history; text; internal format)
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).
LINKS
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

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Last modified April 25 06:49 EDT 2024. Contains 371964 sequences. (Running on oeis4.)