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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

Table of n, a(n) for n=1..4.

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

Adjacent sequences:  A123192 A123193 A123194 * A123196 A123197 A123198

KEYWORD

hard,more,nonn

AUTHOR

Alexander Adamchuk, Oct 04 2006

STATUS

approved

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Last modified February 17 15:32 EST 2020. Contains 331998 sequences. (Running on oeis4.)