# Centering \vdots in Linear Mapping Equations

I am trying to center the vertical dots, but I cant seem to do it - whatever I have tried, the dots remain left aligned. Below is the code that I have at the moment. Any help is greatly appreciated:

\begin{align*}
&T_0: V_0 \mapsto V_1 \\
&T_1: V_1 \mapsto V_2 \\
&T_2: V_2 \mapsto V_3 \\
&\vdotswithin{\mapsto}\\
&T_n: V_n \mapsto V_{n+1}
\end{align*}


• My welcome to the TeX.SE. – Sebastiano Jul 13 at 22:21

Is it something like this you're after?

\documentclass{article}
\usepackage{mathtools}
\usepackage{eqparbox}
\newcommand{\eqmathbox}[2][M] {\eqmakebox[#1]{$\displaystyle#2$}}

\begin{document}

\begin{alignat*}{2}
& T_0 & : V_0 & \mapsto V_1 \\
& T_1 & : V_1 & \mapsto V_2 \\
& \eqmathbox{T_2} & : V_2 & \mapsto V_3 \\[-1.25ex]
& \eqmathbox{\vdots} & &\vdotswithin{\mapsto}\\[-0.5ex]
& T_n & : V_n & \mapsto V_{n+1}
\end{alignat*}

\end{document}


Welcome to TeX-SE! I think you should set the alignment point differently. (\vdotswithin{\mapsto} does not magically search for \mapstos in the other lines and aligns the dots, it just centers them w.r.t. to a box of the corresponding size.)

\documentclass{article}
\usepackage{mathtools}
\begin{document}
\begin{align*}
T_0: V_0 &\mapsto V_1 \\
T_1: V_1 &\mapsto V_2 \\
T_2: V_2 &\mapsto V_3 \\
&\vdotswithin{\mapsto}\\
T_n: V_n &\mapsto V_{n+1}
\end{align*}
\end{document}