% !TeX TXS-program:compile = txs:///pdflatex

\documentclass[margin=5mm]{standalone}
\usepackage[nonpgfplots]{tkz-grapheur}

\begin{document}

\begin{GraphiqueTikz}[x=0.8cm,y=1.3cm,Xmin=0,Ymin=0,Xmax=13.5,Xgrille=2,Xgrilles=2,Ymax=4.3,Ygrilles=1]
  \TracerAxesGrilles*[Origine]{0,2,...,12}{0,1,...,4}
  \ifdef{\TracerNuageSuiteF}%compatibilité dernière version ;-)
    {%
      \TracerNuageSuiteF*[CouleurNuage=red,Style=o,Debut=0,Fin=13]{2}{ln(3*x^2+1)}
    }%
    {%
      \foreach \pt/\val in {
        0/2, 1/2.565, 2/3.032, 3/3.353, 4/3.547, 5/3.657,
        6/3.717, 7/3.748, 8/3.765, 9/3.773, 10/3.778,
        11/3.780, 12/3.781, 13/3.782
      } {
        \filldraw[red] (\pt,\val) circle(1.75pt);
      }
    }%
  \PlacerTexte[Position=right]{(axeox-ee)}{$n$}
  \PlacerTexte[Position=above right]{(axeoy-nn)}{$u_n$}
\end{GraphiqueTikz}

\end{document}