But the fact is that math notation is the most widely known notation for writing down equations (let's make things specific to the OP case and say summation equ

But the fact is that math notation is the most widely known notation for writing down equations (let's make things specific to the OP case and say summation equations and partial derivative equations). Specifically for the superscript case, the vast vast vast majority of the cases, it will be obvious whether the superscript notation means exponentiation or indexing. When there are ambiguities, what the person explaining the equation should do is clarify the ambiguity. It doesn't do the world any good to make the entire engineering world learn (relatively) obscure programming languages in order to be slightly more clear (and let's not forget, much more verbose) when writing down simple equations, when all one has to do is clarify a couple of ambiguities when writing down equations. Let me make it very clear and say this: equations are meant to explain things. They are not standalone pieces of code that you can copy and paste into a REPL. They are tools to explain how something works. You should always have accompanying text that explains what all the variables in the equation mean and clarify unclear notations.