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%I #2 Mar 31 2012 13:20:32
%S 5,7,17,59
%N Numbers n such that A065507[n] = n.
%C A065507[n] is the smallest prime q such that (p^q+1)/(p+1) is a prime, where p = Prime(n).
%e A065507[n] begins {3, 3, 5, 3, 5, 3, 7, 17, 11, 7, 109, 5, 17, 5, 5, 21943, 17,...}.
%e Thus
%e a(1) = 5 because A065507[5] = 5,
%e a(2) = 7 because A065507[7] = 7,
%e a(3) = 17 because A065507[17] = 17.
%Y Cf. A065507.
%K hard,more,nonn
%O 1,1
%A _Alexander Adamchuk_, Oct 04 2006
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