\[ \left\{ \begin{eqnarray*} x'&=&\sigma (-x + y) + \kappa\sin\left(\frac{y}{5}\right) \sin\left(\frac{z}{5}\right) \\ y'&=& -x z + \rho x - y + \kappa\sin\left(\frac{x}{5}\right) \sin\left(\frac{z}{5}\right) \\ z'&=& x y - \beta z + \kappa\cos\left(\frac{y}{5}\right) \cos\left(\frac{x}{5}\right) \end{eqnarray*}\right. \]