Finding the fundamental period by using four elementary operations (+,-,x,/) The idea is to find the fundamental period of any periodic and bounded signal. This is all that we know about the signal. Nothing else. Only allowed operations are: $+,-,\times , \div$. We can also access any value of the signal that we desire. 

How can a method be developed which finds or estimates the fundamental period of the given signal? 

Thank you in advance.
Well eventually operations such as the Fourier Transform and autocorrelation are defined with those four operations.

Are comparisons and conditional decision-making allowed?  Are you allowed to pick a pair of numbers from an array based on one of those numbers being a maximum?

My other answer is a place to begin.