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Card{i<=n, floor(n/i)=0 mod(i)}.
1

%I #9 Jul 10 2015 00:39:34

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

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

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

%N Card{i<=n, floor(n/i)=0 mod(i)}.

%F (1/n)*Sum_{i=1..n} a(i) = C*log(n)+O(log(n)) with C = 0.5...

%o (PARI) for(n=1,150,print1(sum(i=1,n,if(floor(n/i)%i,0,1)),","))

%K nonn

%O 1,4

%A _Benoit Cloitre_, Dec 12 2001