%I #8 Jul 29 2015 00:52:54
%S 2,5,10,15,24,30,43,52,66,78,99,107,132,150,171,188,221,236,273,291,
%T 322,352,397,409,453,489,530,558,615,633,694,727,778,826,883,900,973,
%U 1027,1088,1118,1199,1229,1314,1362,1419,1485,1578,1598,1688,1745,1826,1884
%N a(n) = 2*Sum_{k=1..n} (n+1-k) (Sum_{j|k} 1/floor(n/j)).
%C Sequence consists entirely of integers.
%C First differences give A033885.
%t f[n_] := 2Sum[(n + 1 - k)*Plus @@ (1/Floor[n/Divisors[k]]), {k, n}]; Table[ f[n], {n, 52}] (* _Robert G. Wilson v_, Nov 12 2004 *)
%K nonn
%O 1,1
%A _Leroy Quet_, Nov 09 2004
%E More terms from _Robert G. Wilson v_, Nov 12 2004
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