%I A123488
%S A123488 3,7,31,127,12207031,8191,131071,524287,
%T A123488 1484520425576434196455942238665054573307722183,
%U A123488 10333327940128053377465393536117755205850522803739374960650929
%N A123488 Smallest prime of the form (q^p-1)/(q-1), where p = Prime[n] and q is
prime too (q = A123487[n]).
%C A123488 Corresponding smallest primes q such that (q^p-1)/(q-1) is prime, where
p = Prime[n], are listed in A123487[n] = {2,2,2,2,5,2,2,2,113,151,
2,61,53,89,5,307,19,2,491,...}. a(n) coincides with A084732[n] when
A066180[n] is prime or 0.
%F A123488 a(n) = (A123487[n]^Prime[n] - 1) / (A123487[n] - 1).
%Y A123488 Cf. A123487, A066180, A084732.
%Y A123488 Sequence in context: A000668 A136007 A084732 this_sequence A121620 A042271
A000644
%Y A123488 Adjacent sequences: A123485 A123486 A123487 this_sequence A123489 A123490
A123491
%K A123488 nonn
%O A123488 1,1
%A A123488 Alexander Adamchuk (alex(AT)kolmogorov.com), Sep 30 2006
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