login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A103931 Denominators of squares of harmonic numbers A001008/A002805. 1
1, 4, 36, 144, 3600, 400, 19600, 78400, 6350400, 6350400, 768398400, 768398400, 129859329600, 129859329600, 129859329600, 519437318400, 150117385017600, 16679709446400, 6021375110150400, 240855004406016, 26761667156224 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The corresponding numerators are given in A103930. For the rational see the link there.

LINKS

Table of n, a(n) for n=1..21.

FORMULA

a(n)=denominator(H(n)^2), with the harmonic numbers H(n)=A001008(n)/A002805(n), n>=1.

CROSSREFS

Sequence in context: A204504 A083223 A102263 * A334580 A068589 A120077

Adjacent sequences:  A103928 A103929 A103930 * A103932 A103933 A103934

KEYWORD

nonn,easy,frac

AUTHOR

Wolfdieter Lang, Mar 24 2005

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 15 02:21 EDT 2021. Contains 343909 sequences. (Running on oeis4.)