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a(n) = number of m's among (d(1),d(2),...,d(n)), where m is the maximum value of (d(1),d(2),...,d(n)) and d(n) is the number of divisors of n.
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%I #12 Sep 16 2015 13:13:35

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

%T 2,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,

%U 1,1,1,2,2,2,2,2,2,2,2,2,2,2,2,3,3,3,3,3,3,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5

%N a(n) = number of m's among (d(1),d(2),...,d(n)), where m is the maximum value of (d(1),d(2),...,d(n)) and d(n) is the number of divisors of n.

%e The sequence of the numbers of divisors of the first 11 positive integers is: 1,2,2,3,2,4,2,4,3,4,2.

%e The maximum value obtained here is 4. There are three 4's among (d(1), d(2),...,d(11)); so a(11)=3.

%t a = {}; b = {}; For[n = 1, n < 80, n++, AppendTo[b, Length[Divisors[n]]]; AppendTo[a, Length[Select[b, # == Max[b] &]]]]; a (* _Stefan Steinerberger_, May 18 2008 *)

%Y Cf. A000005, A140223, A140224.

%K nonn

%O 1,3

%A _Leroy Quet_, May 12 2008

%E More terms from _Stefan Steinerberger_, May 18 2008

%E a(78)-a(105) from _Ray Chandler_, Jun 26 2009