2,1

First occurrence of k in A107609.

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

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

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

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

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}]

Cf. A107609, A107614.

Sequence in context: A210710 A225051 A033431 * A091914 A123791 A293620

Adjacent sequences: A107607 A107608 A107609 * A107611 A107612 A107613

nonn

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

approved