A107614 - OEIS

%I #13 Aug 21 2021 13:14:05

%S 1,6,16,42,101,280,657,1663,4107,10229,25333,63321,159135,399855,

%T 1014612,2582128,6592653,16898891,43435899,111985392,289453817,

%U 749973236,1947409123,5067034865,13208284732,34487824962,90192879037

%N Consider the least number n such that n divided by pi(n) rounded is greater than any previous n; a(n) is the denominator of n/pi(n).

%C Lim_{n->infinity} a(n+1)/a(n) ~ e.

%F a(n) = A000720(A107610(n)).

%t 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}]; PrimePi[ g[ # ]] & /@ Range[2, 28]

%Y Cf. A000720, A107609, A107610.

%K nonn

%O 2,2

%A _Jonathan Vos Post_ and _Robert G. Wilson v_, May 17 2005