I need to prove that . The obvious way would be to compare with the series on the r.h.s. which is , but I just can't show that they're the same. Any suggestions?
Follow Math Help Forum on Facebook and Google+
We have when in the second series we have because the sum is empty, so we can write reverting the order of summation
Thank you very much! Your method of dealing with sums has enlightened me.
you're welcome!
View Tag Cloud