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Number of divisors of n that are < log(n).
1

%I #15 May 19 2020 19:13:33

%S 0,0,1,1,1,1,1,2,1,2,1,2,1,2,1,2,1,2,1,2,2,2,1,3,1,2,2,2,1,3,1,2,2,2,

%T 1,3,1,2,2,2,1,3,1,2,2,2,1,3,1,2,2,2,1,3,1,3,2,2,1,4,1,2,2,3,1,3,1,3,

%U 2,2,1,4,1,2,2,3,1,3,1,3,2,2,1,4,1,2,2,3,1,3,1,3,2,2,1,4,1,2,2,3,1,3,1,3,2

%N Number of divisors of n that are < log(n).

%H Antti Karttunen, <a href="/A095999/b095999.txt">Table of n, a(n) for n = 1..65537</a>

%t f[n_] := Length[ Select[ Divisors[ n], # < Log[ n] &]]; Table[ f[n], {n, 105}]

%o (PARI) a(n) = sumdiv(n, d, d<log(n)); \\ _Michel Marcus_, Jun 29 2015

%o (PARI) A095999(n) = sumdiv(n, d, exp(d)<n); \\ _Antti Karttunen_, May 19 2020

%K nonn

%O 1,8

%A _Robert G. Wilson v_, Jul 19 2004, based on a suggestion from _Leroy Quet_, Jun 18 2004