\(\mathop {{\rm{lim}}}\limits_{{\rm{n}} \to - \infty } \left( {\frac{{\rm{n}}}{{{{\rm{n}}^2} + {1^2}}} + \frac{{\rm{n}}}{{{{\rm{n}}^2} + {2^2}}} + \frac{{\rm{n}}}{{{{\rm{n}}^2} + {3^2}}} + \ldots + \frac{1}{{5{\rm{n}}}}} \right)\) is equal to