Consider a two machine proportionate flow shop with n jobs. If X1j = X2j = Dj (deterministic) the makespan is sequence independent. If X1j and X2j are i.i.d. exponential with rate λj, then the expected makespan is sequence independent as well. Consider now a proportionate flow shop with X1j and X2j i.i.d. Erlang(2, λj) with each one of the two phases distributed according to an exponential with rate λj , j = 1, . . . , n. Show via an example that the expected makespan does depend on the sequence.