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 A227629 Least splitter of the harmonic numbers H(n) and H(n+1). 3
 1, 2, 1, 4, 3, 2, 3, 4, 6, 1, 10, 6, 4, 7, 3, 5, 9, 2, 7, 5, 3, 7, 4, 5, 6, 7, 10, 14, 27, 1, 18, 12, 9, 7, 6, 5, 9, 4, 11, 7, 13, 3, 11, 8, 5, 7, 9, 13, 25, 2, 15, 9, 7, 12, 5, 8, 11, 17, 3, 13, 10, 7, 15, 4, 13, 9, 5, 11, 17, 6, 7, 15, 8, 9, 11, 12, 14, 17 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS See A227631 for the definition of least splitter. LINKS Clark Kimberling, Table of n, a(n) for n = 1..1000 EXAMPLE 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 < ... MATHEMATICA 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}]; Denominator[t] (* A227629 *) Numerator[t]   (* A227630 *)  (* Peter J. C. Moses, Jul 15 2013 *) CROSSREFS Cf. A227630, A227631. Sequence in context: A318569 A336280 A277749 * A183201 A082467 A106407 Adjacent sequences:  A227626 A227627 A227628 * A227630 A227631 A227632 KEYWORD nonn,frac AUTHOR Clark Kimberling, Jul 18 2013 STATUS approved

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Last modified September 25 23:23 EDT 2020. Contains 337346 sequences. (Running on oeis4.)