Expand (1-z)^-m in powers of z for m in N. Let (1-z)^-m=sum from n=0 to infinity of (a_nz^n) then
a_n ~n^m-1/(m-1)! as n-> oo where ~ means that the quotient of the expressions to the left and the right of it tends to 1.
Power series are investigated. The solution is detailed and well presented.