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A022819 a(n) = floor(1/(n-1) + 2/(n-2) + 3/(n-3) + ... + (n-1)/1).

%I A022819 #19 Sep 16 2019 18:00:50
%S A022819 0,0,1,2,4,6,8,11,13,16,19,22,25,28,31,34,38,41,44,48,51,55,59,62,66,
%T A022819 70,74,78,81,85,89,93,97,101,106,110,114,118,122,126,131,135,139,144,
%U A022819 148,152,157,161,166,170,174,179,183,188,193,197,202,206,211,216
%N A022819 a(n) = floor(1/(n-1) + 2/(n-2) + 3/(n-3) + ... + (n-1)/1).
%C A022819 a(n) = A214075(n,n-2) for n > 1. - _Reinhard Zumkeller_, Jul 03 2012
%H A022819 Reinhard Zumkeller, <a href="/A022819/b022819.txt">Table of n, a(n) for n = 0..1000</a>
%F A022819 a(n) = floor(sum_{i=2..n} n/i) = floor(A000027(n)*(A001008(n)/A002805(n)-1)) = floor(A006675(n)/A000142(n)) = floor(A001705(n-1)/A000142(n-1)). - _Henry Bottomley_, May 05 2001
%e A022819 a(2) = floor(1/1) = 1;
%e A022819 a(3) = floor(1/2 + 2/1) = floor(5/2) = 2;
%e A022819 a(4) = floor(1/3 + 2/2 + 3/1) = floor(26/6) = 4.
%t A022819 s=0; Table[s+=HarmonicNumber[j]//N; Floor[s],{j,0,5!}] (* _Vladimir Joseph Stephan Orlovsky_, Feb 11 2010 *)
%t A022819 Join[{0},Floor[Accumulate[HarmonicNumber[Range[0,60]]]]] (* _Harvey P. Dale_, Sep 16 2019 *)
%o A022819 (Haskell)
%o A022819 import Data.Ratio ((%))
%o A022819 a022819 n = floor $ sum $ zipWith (%) [1 .. n-1] [n-1, n-2 .. 1]
%o A022819 -- _Reinhard Zumkeller_, Jul 03 2012
%Y A022819 Cf. A027612.
%K A022819 nonn
%O A022819 0,4
%A A022819 _Clark Kimberling_