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a(n) = floor((numerator of H(n))/n), where H(n) = Sum_{k=1..n} 1/k is the n-th harmonic number.
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%I #21 Sep 28 2021 04:07:16

%S 1,1,3,6,27,8,51,95,792,738,7610,7168,88153,83695,79717,152284,

%T 2478954,793016,14489252,2791756,898002,867872,19318117,56159289,

%U 1362100898,1322913164,11575416740,11264449603,318174017634,310156094338

%N a(n) = floor((numerator of H(n))/n), where H(n) = Sum_{k=1..n} 1/k is the n-th harmonic number.

%C Numerator of H(n) is a(n)*n + A126083(n).

%H Amiram Eldar, <a href="/A128437/b128437.txt">Table of n, a(n) for n = 1..2310</a>

%e a(6) = 8 because H(6) = 49/20 and floor(49/6) = 8.

%p H:=n->sum(1/k,k=1..n): a:=n->floor(numer(H(n))/n): seq(a(n),n=1..35); # _Emeric Deutsch_, Mar 22 2007

%t seq = {}; s = 0; Do[s += 1/n; AppendTo[seq, Floor[Numerator[s]/n]], {n, 1, 30}]; seq (* _Amiram Eldar_, Dec 01 2020 *)

%o (PARI) a(n) = numerator(sum(k=1, n, 1/k))\n; \\ _Michel Marcus_, Feb 01 2019

%o (Python)

%o from sympy import harmonic

%o def A128437(n): return harmonic(n).p//n # _Chai Wah Wu_, Sep 27 2021

%Y Cf. A128438, A001008, A126083.

%K nonn

%O 1,3

%A _Leroy Quet_, Mar 03 2007

%E More terms from _Emeric Deutsch_, Mar 22 2007