====== Lecture 8 ======
More about series following Rudin
  * Thm 3.39: radius of convergence for power series
  * Summation by part.Thm 3.41, Thm 3.42, Thm 3.44
  * Rearrangement theorem of Riemann

Discussion: 
  * Rudin's exercises in Ch 3, 6,7,9,11