This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A104174 #25 Feb 16 2025 08:32:56
%S A104174 0,1,5,1,17,9,83,201,2089,2341,551,2861,64913,90653,114677,274399,
%T A104174 5385503,2022061,42503239,9276623,3338549,3573693,87368107,276977179,
%U A104174 7281378067,7624597867,71595952403,74464289303,2239777822987
%N A104174 Numerator of the fractional part of a harmonic number.
%H A104174 Clark Kimberling, <a href="/A104174/b104174.txt">Table of n, a(n) for n = 1..1000</a>
%H A104174 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/BookStackingProblem.html">Book Stacking Problem.</a>
%F A104174 a(n) = numerator(frac(Sum_{k=1..n} 1/k)). [edited by _Michel Marcus_, Sep 27 2021]
%t A104174 h[n_] := Sum[1/k, {k, 1, n}]
%t A104174 Table[Numerator[FractionalPart[h[n]]], {n, 1, 30}]
%t A104174 (* _Clark Kimberling_, Aug 13 2012 *)
%t A104174 FractionalPart[HarmonicNumber[Range[30]]]//Numerator (* _Harvey P. Dale_, Jul 28 2019 *)
%o A104174 (Python)
%o A104174 from sympy import harmonic
%o A104174 def A104174(n): return (lambda x: x.p % x.q)(harmonic(n)) # _Chai Wah Wu_, Sep 26 2021
%o A104174 (PARI) a(n) = numerator(frac(sum(k=1, n, 1/k))); \\ _Michel Marcus_, Sep 27 2021
%Y A104174 Cf. A064169, A075135.
%K A104174 nonn
%O A104174 1,3
%A A104174 Georg Haass (geha5001(AT)stud.uni-saarland.de), Mar 10 2005