Hi My calculus textbook is completely crap at explaining recurrence relations. I know the theorems needed to solve difference equations analytically, but I do not understand why they are true. What websites and/or books can I read to get a better intuitive understanding of recurrence relations? PS. I am not asking how to solve some specific type of recurrence relation. Homogeneous, non-homogeneous, linear, non-linear, first-order and second order recurrence relations are all relevant.