TeX/Latex - Colorear cada letra con colores distintos

%%%codigo para colorear logotipo LaTeX

\makeatletter

\newcommand*\ClrTeX[3]{%

  \textcolor{#1}{T}\kern-.1667em%

  \lower.5ex\hbox{\textcolor{#2}{E}}\kern-.125em\textcolor{#3}{X}\@}

\newcommand*\ClrLaTeX[5]{%

  \textcolor{#1}{L}\kern-.36em%

  {\sbox\z@ T%

     \vbox to\ht\z@{\hbox{\check@mathfonts

    \fontsize\sf@size\z@

    \math@fontsfalse\selectfont

    \textcolor{#2}{A}}%

    \vss}%

  }%

  \kern-.15em%

  \ClrTeX{#3}{#4}{#5}}

\newcommand*\ClrLaTeXe[7]{%

  \mbox{\m@th

    \if b\expandafter\@car\f@series\@nil\boldmath\fi

    \ClrLaTeX{#1}{#2}{#3}{#4}{#5}\kern.15em%

    \textcolor{#6}{2}$_{\textstyle\textcolor{#7}{\varepsilon}}$}}

\makeatother

%%%%%fin del codigo

\begin{document}

\scalebox{2.5}{ \huge \ClrLaTeX{red}{green!80!black}{blue}{orange}{yellow!80!black} \textcolor{gray}{2017}}

\end{document}