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Primes whose indices are perfect numbers.
0

%I #6 Jan 23 2023 09:04:40

%S 13,107,3541,83243,645072299,215186133599,3839719253921

%N Primes whose indices are perfect numbers.

%F a(n) = A000040(A000396(n)).

%e a(1)=13 because the first perfect number is 6 and the 6th prime is 13.

%e a(2)=107 because the second perfect number is 28 and the 28th prime is 107.

%Y Cf. A000040, A000396.

%K hard,more,nonn

%O 1,1

%A _Omar E. Pol_, Dec 09 2009

%E More terms from _Omar E. Pol_ and _Max Alekseyev_, Dec 10 2009