Let R ={ a, b, c, d, e } and S ={1,2,3,4}. Total number of onto functions f: R → S such that f( a ) ≠ 1, is equal to ____.

Let $\displaystyle \mathrm{R}=\{\mathrm{a}, \mathrm{b}, \mathrm{c}, \mathrm{d}, \mathrm{e}\}$ and $\displaystyle \mathrm{S}=\{1,2,3,4\}$. Total number of onto functions $\displaystyle f: \mathrm{R} \rightarrow \mathrm{S}$ such that $\displaystyle f(\mathrm{a}) \neq 1$, is equal to $\displaystyle \_\_\_\_$.