A084297 Primes p=prime(m) such that pi(m*p)/m is an integer.

2, 5, 211, 457, 1223, 3943, 130259, 167953, 468473, 721159, 927317, 2026061, 7066487

Offset: 1

Author

Labos Elemer, May 27 2003

Keywords

• nonn
• more

Crossrefs

Cf. A000040, A000720, A057855, A084295.

Programs

Mathematica

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

Formula

a(n) = prime(A084295(n)).

Extensions

Name edited by Michel Marcus, Aug 30 2019

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

a(13) from Chai Wah Wu, May 14 2020