Let S N $\cup$ {0}. Define a relation R from S to R by: $\mathbf{R}=\left\{(\mathrm{x},\mathrm{y}):{\log }_{\mathrm{e}}\mathrm{y}={\mathrm{xlog}}_{\mathrm{e}}\left(\frac{2}{5}\right),\mathrm{x}\in \mathrm{S},\mathrm{y}\in \mathbf{R}\right\}.$ Then, the sum of all the elements in the range of R is equal to