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.

A104174 Numerator of the fractional part of a harmonic number.

Original entry on oeis.org

0, 1, 5, 1, 17, 9, 83, 201, 2089, 2341, 551, 2861, 64913, 90653, 114677, 274399, 5385503, 2022061, 42503239, 9276623, 3338549, 3573693, 87368107, 276977179, 7281378067, 7624597867, 71595952403, 74464289303, 2239777822987
Offset: 1

Views

Author

Georg Haass (geha5001(AT)stud.uni-saarland.de), Mar 10 2005

Keywords

Crossrefs

Programs

  • Mathematica
    h[n_] := Sum[1/k, {k, 1, n}]
    Table[Numerator[FractionalPart[h[n]]], {n, 1, 30}]
    (* Clark Kimberling, Aug 13 2012 *)
    FractionalPart[HarmonicNumber[Range[30]]]//Numerator (* Harvey P. Dale, Jul 28 2019 *)
  • PARI
    a(n) = numerator(frac(sum(k=1, n, 1/k))); \\ Michel Marcus, Sep 27 2021
  • Python
    from sympy import harmonic
    def A104174(n): return (lambda x: x.p % x.q)(harmonic(n)) # Chai Wah Wu, Sep 26 2021
    

Formula

a(n) = numerator(frac(Sum_{k=1..n} 1/k)). [edited by Michel Marcus, Sep 27 2021]