The fact that it appears to hang is an interesting observation, but you should run it longer than 20 minutes to be sure. Maybe leave it running overnight? The real problem is that I don't even want to evaluate that sum. Maple tries to evaluate that sum inside another of its own procedures and gets stuck, so I have no control over it. My real problem is the following program: restart; rq:=Q(n+1)=Q(n)/x+4*(n+1)^2*Q(n)+4/3/x*n*(n+1)*(n+1/2); Ans:=rsolve(rq,Q(n)); and Maple freezes inside "rsolve". I speculate that it is trying to evaluate the sum I previously posted, which happens to be the answer. When you run the above program, does it freeze after about 20 minutes? By freeze, I mean a complete halt - nonresponsive cursor and keyboard. Sometimes the machine spontaneously reboots instead of freezing. Otherwise it might still be trying to solve the problem after 20 minutes and it will eventually emerge. Thanks Mike

Sorry, I don't understand your comment. The sum is from 0 to n-1 not n..n-1, and it was Maple itself that generated the statement in question. When run on my machine, Maple produces nothing except a CPU freeze. Does it freeze when run on your computer?

Sorry, I don't understand your comment. The sum is from 0 to n-1 not n..n-1, and it was Maple itself that generated the statement in question. When run on my machine, Maple produces nothing except a CPU freeze. Does it freeze when run on your computer?

Thanks. I had already tried "assuming" but that doesn't work because the original expression (as opposed to the simple test I posted) was calculated from the solution of a complicated set of equations and the "assuming" command didn't appear to propogate into the interior of "solve", so I kept getting the wrong answer. But I never met the "indets" command before, so thank you for that. Subsidiary question: can you always assume that the variable you are looking for will be the 5'th entry in the indets list as in your example? Otherwise, a program (as opposed to a one-off calculation with a human at the helm) would have to search the indets list for the desired variable, and that brings us back to square 1. Michael

Thanks. I had already tried "assuming" but that doesn't work because the original expression (as opposed to the simple test I posted) was calculated from the solution of a complicated set of equations and the "assuming" command didn't appear to propogate into the interior of "solve", so I kept getting the wrong answer. But I never met the "indets" command before, so thank you for that. Subsidiary question: can you always assume that the variable you are looking for will be the 5'th entry in the indets list as in your example? Otherwise, a program (as opposed to a one-off calculation with a human at the helm) would have to search the indets list for the desired variable, and that brings us back to square 1. Michael

Hi: There is a program called PDFCreator which you can pick up from various sources on the internet. It comes with the gnu licence so it is essentially free, but some people have taken to packaging it in a simple form and selling it for $5 on ebay. Anyway, it will convert any print operation into a PDF file, and it works nicely. So, with that program installed, just highlight whatever you want from a Maple worksheet, or the worksheet itself, and print it. Choose PDFCreator, instead of your default printer. You will end up with a .PDF file. Michael

Thanks. Could you please clarify: Under what conditions does (b^u)* (b^v) not equal b^(u+v) when b,u, and v are all complex? Thanks Michael

Thanks. Could you please clarify: Under what conditions does (b^u)* (b^v) not equal b^(u+v) when b,u, and v are all complex? Thanks Michael