Hi, I was reading a derivation over at mathworld.wolfram and I struck something that looks simple enough but I cant quite see it. I think it might be a mistake in the web-page but I'd just like to get second (or 3rd 4th etc) opinion on it. The page in question is here : http://mathworld.wolfram.com/RiemannZetaFunction.html I know there's some heavy stuff on that page but trust me that my issue is a fairly simple one. If you scroll down past the preamble and graphs until you come to the numbered equations, the part I have an issue with is in equations 1 through to 7. Specifically the part where it says "If x is an integer n, then we have the identity" (just after numbered equation 1). In that section from equation 1 through 7 I just can't see anything at all that would require x be restricted to integers. Is it just me or do you think that the page is in error when it suggests that x needs to be an integer here? Thanks in advance.