%!TEX pdflatex
\documentclass[margin=1cm]{standalone}
\usepackage{ProfLycee}
\tikzset{
cross/.pic = {
\draw[rotate = 45] (-#1,0) -- (#1,0);
\draw[rotate = 45] (0,-#1) -- (0, #1);
}
}
\begin{document}
\begin{tikzpicture}[x=0.6cm,y=4cm,xmin=0,xmax=12,ymin=0,ymax=1.25,xgrille=1,xgrilles=1,ygrilles=0.1]
\GrilleTikz
\AxesTikz \AxexTikz{0,1,...,12} \AxeyTikz{0,1}
\foreach \x in {0,1,...,12} \draw[thick] ({\x},{(1/2)^(\x)}) pic[red] {cross=3pt} ;
\end{tikzpicture}
\end{document}