"Hello, We are an intelligent race". This type of message was clearly created. The message was sent using a series of tones of constant length, repeating ad infinitum (with a 36 chr. pause in between) for a day or so, showing that they are there, and that we aren't picking up "I Love Lucy" (or equivalent) bouncing around off interstellar debris, that this is indeed an intentional attempt to communicate with whomever is out there. Then, they send counting, arithmetic, etc. Math is probably the most universal language (as an example, it is something developed by virtualy all tribes on Earth), and if any kind of discussion is to take place, math is probably the most basic. Sure, sending "1 1=2" across the cosmos isn't exactly a fantastic discovery (hopefully anybody smart enough to build a radio reciever will know that), but if we start with "e=mc^2" and "e^((i)(pi))-1=0", the other guys will have no idea what in hell's name we are trying to say. In addition to the fact that an intelligent lifeform capabale of constructing a big radio transmitter, and clever (and like-minded enough) to send a logical, simple message is good, and if we can figure out the rest of the message, we are that much better off. By sending more basic stuff, the T.Cians (T.Cites?) have increased the chance that we can figure out the rest of the message.