login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A107610 Least number n such that n divided by Pi(n) rounded is greater than any previous n. 2
2, 16, 56, 190, 556, 1821, 4928, 14136, 39017, 107405, 291330, 791513, 2148323, 5797898, 15726486, 42605113, 115371428, 312629484, 847000031, 2295700537, 6223257066, 16874397811, 45764114391, 124142354193, 336811260666 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

COMMENTS

First occurrence of k in A107609.

Lim_n->inf. a(n+1)/a(n)=~e.

LINKS

Table of n, a(n) for n=2..26.

FORMULA

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

EXAMPLE

a(2)=16 because round(16/6)=3 and for no other number less than 16 does the quotient equal 3.

MATHEMATICA

f[n_] := Round[ n / PrimePi[ n]]; g[2] = 2; g[n_] := g[n] = Block[{k = PrimePi[E g[n - 1]]}, While[ f[k] < n, k++ ]; k]; Do[ Print[ g[ n]], {n, 2, 26}]

CROSSREFS

Cf. A107609, A107614.

Sequence in context: A210710 A225051 A033431 * A091914 A123791 A293620

Adjacent sequences:  A107607 A107608 A107609 * A107611 A107612 A107613

KEYWORD

nonn

AUTHOR

Jonathan Vos Post and Robert G. Wilson v, May 17 2005

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified September 18 20:07 EDT 2019. Contains 327181 sequences. (Running on oeis4.)