A107609 - OEIS

A107609

a(n) = round(n / pi(n)) = round(A000027(n) / A000720(n)).

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

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OFFSET

2,1

COMMENTS

This sequence grows very slowly. The first n for which a(n) = 5 is 190, then 556 for 6, 1821 for 7, etc. - Alonso del Arte, Feb 27 2012

LINKS

Table of n, a(n) for n=2..106.

EXAMPLE

a(6) = 2 because pi(6) = 3 and 6/3 = 2.

a(7) = 2 because pi(7) = 4 and 7/4 = 1.75, which rounds up to 2.

MATHEMATICA

Table[ Round[ n / PrimePi[ n]], {n, 2, 106}]