wrong distribution of an even number of dots [duplicate]

Question

Working on my answer to Better way of designing memory layout in tikz I've found that the distribution of a number of consecutive \bullet (or \cdot) is different if the number is even or odd. Space between two last elements in an even list is shorter. Why? How could it be corrected?

\documentclass{article}
\usepackage{pgffor} 

\newcommand{\mydots}[1]{$\foreach\i in {1,...,#1}{\bullet}$}

\begin{document}
\foreach\i in {1,...,15}
{\noindent\mydots{\i}\\}
\end{document}

Answer 1

try:

\documentclass{article}
\usepackage{pgffor}

\newcommand{\mydots}[1]{$\foreach\i in {1,...,#1}{\bullet}{}$}% <-- added {}

\begin{document}
\foreach\i in {1,...,15}
{\noindent\mydots{\i}\\}
\end{document}

edit:

• as explained in Torbjørn T. comment, \bullet is binary opreator
• it can also be solved by using \mathop{\bullet} as say Ignasy

• or for `\mydots use beside my first proposition also with:

  \newcommand{\mydots}[1]{\foreach\i in {1,...,#1}{\textbullet\ }}