Functions

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