A165689 Numbers n such that pi(n) = (1/10)*n.

64540, 64580, 64610, 64620, 64650, 64690, 64700, 64710, 64720

Offset: 1

Author

Farideh Firoozbakht, Oct 06 2009

Keywords

• fini
• full
• nonn

Comments

A subsequence of A057809. For each positive integer m, set of the numbers n such that pi(n)=(1/10^m)*n is a finite set. I guess that all these sets are nonempty. What is the smallest number n such that pi(n) = (1/100)*n?

Crossrefs

Cf. A057809.

Programs

Mathematica

Select[10 Range[10000], PrimePi[ # ] == 1/10 # &]

PARI

forcomposite(n=1, 1e5, if(10*primepi(n) == n, print1(n, ", "))) \\ Altug Alkan, Dec 18 2015