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A084297 Primes p=prime(m) such that pi(m*p)/m is integer. 2
2, 5, 211, 457, 1223, 3943, 130259, 167953, 468473, 721159, 927317, 2026061 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..12.

FORMULA

a(n) = prime(A084294(n))

MATHEMATICA

Do[s=PrimePi[n*Prime[n]]/n; If[IntegerQ[s], Print[Prime[n]]], {n, 1, 100000}]

CROSSREFS

Cf. A000040, A000720, A057855, A084294, A084298.

Sequence in context: A216458 A027682 A096695 * A041873 A072118 A249180

Adjacent sequences:  A084294 A084295 A084296 * A084298 A084299 A084300

KEYWORD

nonn,more

AUTHOR

Labos Elemer, May 27 2003

EXTENSIONS

Name edited by Michel Marcus, Aug 30 2019

a(9)-a(12) from Giovanni Resta, Sep 02 2019

STATUS

approved

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Last modified January 22 07:39 EST 2020. Contains 331139 sequences. (Running on oeis4.)