General equation of a random walk with absorbing barriers

[Poirot1]

What is the general equation of a random walk with :

a) modified random walk

b) absorbing barriers

c) simple symmetric

 

[CaptainBlack]

What is the general equation of a random walk with :

a) modified random walk

b) absorbing barriers

c) simple symmetric

It is probably too late, but please be more specific. What are you interested in; the transition matrix of a discrete random walk? The distribution after n steps? ...

One reason posts do not get a response is the the question is too vague, or general.

CB