A127267 a(n) = floor(n/pi(n)), where pi(n)=A000720(n) is the number of primes <=n.

2, 1, 2, 1, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 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, 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, 3, 3, 3, 4, 3, 3, 3, 3, 3, 3

Offset

2,1

Links

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

Formula

a(n) = A097456(n) + 1. - Filip Zaludek, Dec 16 2016

Example

a(28)=3 because there are 9 primes not exceeding 28 (namely, 2,3,5,7,11,13,17,19,23) and floor(28/9)=3.

Maple

with(numtheory): a:=n->floor(n/pi(n)): seq(a(n), n=2..140); # Emeric Deutsch, Apr 15 2007

Mathematica

Table[Floor[n/PrimePi@ n], {n, 2, 120}] (* Michael De Vlieger, Dec 17 2016 *)

Prog

(PARI) a(n) = n\primepi(n); \\ Michel Marcus, Dec 16 2016

Crossrefs

Cf. A000720.

Sequence in context: A338650 A033105 A106703 * A268173 A008617 A339369

Adjacent sequences: A127264 A127265 A127266 * A127268 A127269 A127270

Keyword

nonn

Author

Leroy Quet, Mar 27 2007

Extensions

More terms from Emeric Deutsch, Apr 15 2007

Status

approved