A272231 a(n) = round(n / pi(n)), where pi(n) is the prime-counting function.

2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 3, 3, 2, 3, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 3, 4, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4

Offset: 2

Author

Benjamin Przybocki, Apr 22 2016

Keywords

• nonn

Comments

This sequence grows slowly; a(n) reaches 10 at n = 39017.

Crossrefs

Cf. A000720, A064658, A107609.

Programs

Mathematica

Table[Round[n/PrimePi@ n], {n, 2, 120}] (* Michael De Vlieger, May 20 2016 *)

PARI

n \/ primepi(n) \\ Charles R Greathouse IV, Apr 30 2016

Formula

a(n) = round(n / pi(n)).

a(n) ~ log(n). - Charles R Greathouse IV, Apr 30 2016