\begin {tabular}{cc}%
dof&error1\\%
\pgfutilensuremath {4}&\pgfutilensuremath {0.25}\\%
\pgfutilensuremath {16}&\pgfutilensuremath {6.25\cdot 10^{-2}}\\%
\pgfutilensuremath {64}&\pgfutilensuremath {1.56\cdot 10^{-2}}\\%
\pgfutilensuremath {256}&\pgfutilensuremath {3.91\cdot 10^{-3}}\\%
\pgfutilensuremath {1{,}024}&\pgfutilensuremath {9.77\cdot 10^{-4}}\\%
\pgfutilensuremath {4{,}096}&\pgfutilensuremath {2.44\cdot 10^{-4}}\\%
\pgfutilensuremath {16{,}384}&\pgfutilensuremath {6.1\cdot 10^{-5}}\\%
\pgfutilensuremath {65{,}536}&\pgfutilensuremath {1.53\cdot 10^{-5}}\\%
\pgfutilensuremath {2.62\cdot 10^{5}}&\pgfutilensuremath {3.81\cdot 10^{-6}}\\%
\pgfutilensuremath {1.05\cdot 10^{6}}&\pgfutilensuremath {9.54\cdot 10^{-7}}\\%
\end {tabular}%