Define the double factorial of n, denoted , as follows: ={1⋅3⋅5(n−2)⋅nif n is odd 2⋅4⋅6(n−2)⋅nif n is even and (−1)==1. find the radius of convergence for the given power series. ∑n=1[infinity]3n⋅n! ⋅(5n+8)! ⋅(2n)⋅[(n+9)! ]5⋅(4n−4)(−6x+4)n the radius of convergence, r