cp's OEIS Frontend

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.

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A227684 Numerator of least splitting rational of log(n) and log(n+1).

Original entry on oeis.org

0, 1, 4, 3, 5, 9, 2, 13, 9, 7, 12, 5, 13, 8, 11, 14, 17, 29, 53, 3, 34, 25, 19, 16, 13, 23, 33, 10, 17, 24, 31, 52, 7, 39, 25, 18, 29, 51, 11, 37, 26, 15, 34, 19, 42, 23, 27, 31, 39, 47, 59, 83, 135, 4, 161, 97, 69, 53, 45, 41, 33, 29, 54, 25, 46, 21, 59, 38
Offset: 1

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Author

Clark Kimberling, Jul 19 2013

Keywords

Comments

Suppose that x < y. The least splitter of x and y is introduced at A227631 as the least positive integer d such that x <= c/d < y for some integer c; the number c/d is called the least splitting rational of x and y.

Examples

			The splitting rationals of consecutive numbers log(1), log(2), ... are 0, 1, 4/3, 3/2, 5/3, 9/5, 2, 13/6, 9/4, 7/3, 12/5, 5/2, 13/5; the denominators form A227634, and the numerators, A227684.  Chain:
log(1) <= 0 < log(2) < 1 < log(3) < 4/3 < log(4) < 3/2 < log(5) < 5/3 < ...
		

Crossrefs

Programs

  • 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[Log[n], Log[n + 1]], {n, 1, 120}] (*fractions*)
    Denominator[t] (* A227634 *)
    Numerator[t]  (* A227684 *)
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