please forgive me if this question is not a good one, I am just a high school student (note: this isn't homework).
I was wondering if every sequence of integers could be represented by an explicit equation.
I have read another similar question whose answer mentions a "Lagrange Interpolating Polynomial", but how would you find this polynomial? And what is the maximum length of sequence this works for?
Edit: I am specifically wondering how one would find an equation that fits, say 20, points, with the y values being randomly chosen integers. how would one go about finding this equation, and is this practical?
Thank you in advance for any answers.