Multi-Rocket Thought Experiment

We consider $n $\underline {\textit{\textgreater }}\textit{ 2} identical rockets: $R_{1}, R_{2}$\textit{, \textellipsis , R}$_{n}$. Each of them moving at constant different velocities respectively $v_{1}, v_{2}$\textit{, \textellipsis , v}$_{n}$ on parallel directions in the same sense. In each rocket there is a light clock, the observer on earth also has a light clock. All $n +$\textit{ 1} light clocks are identical and synchronized. The proper time $\Delta t'$ in each rocket is the same. \begin{enumerate} \item If we consider the observer on earth and the first rocket $R_{1}$, then the non-proper time \quad $\Delta t$ of the observer on earth is dilated with the factor $D(v_{1}):$ \end{enumerate} or \quad $\Delta t = \quad \Delta t'D(v_{1}) $ \begin{enumerate} \item But if we consider the observer on earth and the second rocket $R_{2},$ then the non-proper time \quad $\Delta t$ of the observer on earth is dilated with a different factor $D(v_{2}):$ \end{enumerate} or $\Delta t = \quad \Delta t'D(v_{2}) $ And so on. Therefore simultaneously \quad $\Delta t$ is dilated with different factors $D(v_{1}), D(v_{2}$\textit{), \textellipsis , D(v}$_{n}),$ which is a multiple contradiction.