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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.

A227630 Numerator of the least splitting rational of the harmonic numbers H(n) and H(n+1).

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%I A227630 #5 Dec 04 2016 19:46:32
%S A227630 1,3,2,9,7,5,8,11,17,3,31,19,13,23,10,17,31,7,25,18,11,26,15,19,23,27,
%T A227630 39,55,107,4,73,49,37,29,25,21,38,17,47,30,56,13,48,35,22,31,40,58,
%U A227630 112,9,68,41,32,55,23,37,51,79,14,61,47,33,71,19,62,43,24
%N A227630 Numerator of the least splitting rational of the harmonic numbers H(n) and H(n+1).
%C A227630 See A227631 for the definition of least splitting rational.
%H A227630 Clark Kimberling, <a href="/A227630/b227630.txt">Table of n, a(n) for n = 1..1000</a>
%e A227630 The first few splitting rationals are 1/1, 3/2, 2/1, 9/4, 7/3, 5/2, 8/3, 11/4, 17/6, 3/1, 31/10, 19/6; e.g. 9/4 splits H(4) and H(5), as indicated by H(4) = 1 + 1/2 + 1/3 + 1/4 =  2.083...  < 2.25 < 2.283... = H(5) and the chain H(1) <= 1/1 < H(2) < 3/2 < H(3) < 2/1 < H(4) < 9/4 < ...
%t A227630 h[n_] := h[n] = HarmonicNumber[n]; r[x_, y_] := Module[{c, d}, d = NestWhile[#1 + 1 &, 1, ! (c = Ceiling[#1 x - 1]) < Ceiling[#1 y] - 1 &]; (c + 1)/d]; t = Table[r[h[n], h[n + 1]], {n, 1, 120}];
%t A227630 Denominator[t] (* A227629 *)
%t A227630 Numerator[t]   (* A227630 *)  (* _Peter J. C. Moses_, Jul 15 2013 *)
%Y A227630 Cf. A227629, A227631.
%K A227630 nonn,frac
%O A227630 1,2
%A A227630 _Clark Kimberling_, Jul 18 2013