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a(n) = number of k, 1 <= k <= n, such that k divides ceiling(n/k).
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%I #8 Feb 01 2019 16:25:55

%S 1,1,2,2,1,1,3,3,2,1,2,2,2,2,3,4,2,2,2,2,2,2,3,3,3,2,3,2,2,2,4,4,2,3,

%T 4,4,1,1,2,2,1,1,4,4,4,4,5,5,3,2,2,3,2,2,2,2,2,2,3,3,4,4,5,4,1,1,3,3,

%U 2,3,5,5,3,3,4,3,3,3,5,5,3,1,2,2,1,1,2,3,2,2,3,4,4,4,5,6,5,5,5,4,1,1,3,3,2

%N a(n) = number of k, 1 <= k <= n, such that k divides ceiling(n/k).

%e Ceiling(n/k) for n = 7 is: k=1: 7; k=2: 4; k=3: 3; k=4: 2; k=5: 2; k=6: 2; k=7: 1. 1 divides 7, 2 divides 4, 3 divides 3; so a(7) = 3.

%p a:=proc(n) local ct,k: ct:=0: for k from 1 to n do if type(ceil(n/k)/k, integer)=true then ct:=ct+1 else ct:=ct fi od: ct; end: seq(a(n),n=1..130); # _Emeric Deutsch_, Mar 28 2007

%Y Cf. A066030.

%K nonn

%O 1,3

%A _Leroy Quet_, Mar 02 2007

%E More terms from _Emeric Deutsch_, Mar 28 2007