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Floor(sum_{i=2..n} 1/(i*log(i))).
0

%I #9 Nov 15 2013 00:20:44

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

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

%U 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2

%N Floor(sum_{i=2..n} 1/(i*log(i))).

%C Compare with sum_{i=1..n} 1/prime(n).

%C This sequence also appears to diverge, with a(n) >= 3 for n >= 8718.

%t s = 0; Table[Floor[s = s + 1/(n*Log[n])], {n, 2, 88}] (* _T. D. Noe_, Nov 15 2013 *)

%o (JavaScript)

%o s=0;

%o for (i=2;i<600;i++) {

%o s+=1/(i*Math.log(i));

%o document.write(Math.floor(s)+", ");

%o }

%Y Cf. A000040 (the primes).

%K nonn

%O 2,27

%A _Jon Perry_, Nov 11 2013