How to change indeces of Sums created by powerseries?



Hi all,

my maxima installation uses I1-I* to name indeces of SUMs created by 
powerseries:

                             INF
                             ====        I1  2 I1
                             \      (- 1)   x
(%o1)                         >     -------------
                             /         (2 I1)!
                             ===
                             I1 = 0

How do I change those I1 into "n" or maybe "k" ???

Any help?

Thx

Greetings
	-- Fabian Schuh