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\begin{center}
\vskip 1cm{\LARGE\bf Errata for the Paper\\
\vskip .11in
``Weighted Gcd-Sum Functions''} 
\vskip 1cm 
\large
L\'aszl\'o T\'oth  \\
Department of Mathematics \\
University of P\'ecs \\
Ifj\'us\'ag u. 6 \\
7624 P\'ecs \\
Hungary  \\
\href{mailto:ltoth@gamma.ttk.pte.hu}{\tt ltoth@gamma.ttk.pte.hu}\\
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The  paper \cite{Tot2011} contains some errors. Let

\begin{equation*}
P_{\bino}(n):= \sum_{k=1}^n  \binom{n}{k} \gcd(k,n) \qquad (n\in
\N).
\end{equation*}

In identity (26) of \cite[Prop.\ 9]{Tot2011},
in its proof (second to last line of page 6)
and in identity (28) of \cite{Tot2011} the exponent of $-1$ is
$\ell n/d$ instead of $\ell$. I thank Max Alekseyev for pointing this out.

The correct form of (26) is the following. For every $n\in \N$,
\begin{equation*}
P_{\bino}(n)= 2^n \sum_{d\mid n} \frac{\phi(d)}{d} \sum_{\ell=1}^d
(-1)^{\ell n/d} \cos^n (\ell\pi/d) -n.
\end{equation*}

The correct form of (28) is
\begin{equation*}
R_{\bino}(n):= \sum_{\substack{k=1\\ \gcd(k,n)=1}}^n \binom{n}{k}=
2^n \sum_{d\mid n} \frac{\mu(d)}{d} \sum_{\ell=1}^d (-1)^{\ell n/d}
\cos^n (\ell\pi/d) \qquad (n>1).
\end{equation*}

Furthermore, in the right hand side of identity (35) of \cite[Prop.\ 13]{Tot2011}
the term $n$ is missing. The correct form of (35) is the following.
For every $n\in \N$ and $\alpha \in \R$,
\begin{equation*}
P_{\flooro}(n):=\sum_{k=1}^n  \left \lfloor \alpha + \frac{k}{n}
\right \rfloor \gcd(k,n) = \sum_{d\mid n} \phi(d) \left \lfloor
\frac{n\alpha}{d} \right \rfloor + n.
\end{equation*}

Also, in the right hand side of identity (39) the term $1$ is missing. The correct form of (39) is
\begin{equation*}
\sum_{k=1}^n \left \lfloor \alpha+ \frac{k}{n} \right \rfloor =
\left \lfloor n \alpha \right \rfloor +1 \qquad (n\in \N).
\end{equation*}

\begin{thebibliography}{9}

\bibitem{Tot2011} L.~T\'oth, Weighted gcd-sum functions, {\it J. Integer Seq.}
{\bf 14} (2011),
\href{http://www.cs.uwaterloo.ca/journals/JIS/VOL14/Toth/toth9.html}{Article
11.7.7}.
\end{thebibliography}

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