Unitary harmonic numbers
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- by Peter Hagis and Graham Lord PDF
- Proc. Amer. Math. Soc. 51 (1975), 1-7 Request permission
Abstract:
If ${d^ \ast }(n)$ and ${\sigma ^ \ast }(n)$ denote the number and sum, respectively, of the unitary divisors of the natural number $n$ then the harmonic mean of the unitary divisors of $n$ is given by ${H^ \ast }(n) = n{d^ \ast }(n)/{\sigma ^ \ast }(n)$. Here we investigate the properties of ${H^ \ast }(n)$, and, in particular, study those numbers $n$ for which ${H^ \ast }(n)$ is an integer.References
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Additional Information
- © Copyright 1975 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 51 (1975), 1-7
- MSC: Primary 10A20
- DOI: https://doi.org/10.1090/S0002-9939-1975-0369231-9
- MathSciNet review: 0369231