We now show that the partial probabilities
at time t can be
calculated in terms of the
's at time t-1.
Consider the trellis below :
We consider calculating the most probable path to the state X at
time t; this path to X will have to pass through one of the
states A, B or C at time (t-1).
's at time t ( > 1 )![[Picture]](graphics/abcxtrellis.gif)