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A123488 Smallest prime of the form (q^p-1)/(q-1), where p = prime(n) and q is also prime (q = A123487(n)). 3

%I

%S 3,7,31,127,12207031,8191,131071,524287,

%T 1484520425576434196455942238665054573307722183,

%U 10333327940128053377465393536117755205850522803739374960650929

%N Smallest prime of the form (q^p-1)/(q-1), where p = prime(n) and q is also prime (q = A123487(n)).

%C Corresponding smallest primes q are listed in A123487.

%C a(n) coincides with A084732(n) when A066180(n) is prime or 0.

%F a(n) = (A123487(n)^prime(n) - 1) / (A123487(n) - 1).

%Y Cf. A123487, A066180, A084732.

%K nonn

%O 1,1

%A _Alexander Adamchuk_, Sep 30 2006

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Last modified April 14 05:00 EDT 2021. Contains 342941 sequences. (Running on oeis4.)