<disclaimer> I know very little about this sort of thing and I am ADAMANT to avoid doing any actual scholastic research on it. That's the point of me doing stuff like this; I want to see how much I can learn from effectively no experience, just by messing around and asking for peer review.</disclaimer>
So, my conjecture is that if I was to connect an infinite number of AC sources that harmonise with each other in series, and set the amplitudes so that the amplitudes at each junction between the sources is equal, then connect each junction in parallel with equal resistance from each, the resulting waveform would be a perfect square wave at the root frequency.
