A251965 - OEIS

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A251965

Indices of primes in A055729(m), where A055729(m) is the number of primes <= 3^m.

0

1, 5, 11, 13, 14, 31

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OFFSET

1,2

COMMENTS

A055729 is the sequence primepi(3^n). A087865 are the terms of A055729 that are prime. a(n) is the index of the n-th prime term in A055729.

LINKS

Table of n, a(n) for n=1..6.

EXAMPLE

1 is a term since A055729(1) = 2 is prime.

The next prime appearing in A055729 is 53, which occurs at index 5, so a(2)=5.

MATHEMATICA

Select[Range@49, PrimeQ[PrimePi[3^#]]&]

CROSSREFS

Cf. A055729, A087865.

Sequence in context: A104215 A287123 A227146 * A093685 A337658 A206548

Adjacent sequences: A251962 A251963 A251964 * A251966 A251967 A251968

KEYWORD

nonn,more

AUTHOR

David Baugh, Mar 21 2015

STATUS

approved