I'm a mathematics undergraduate interested in theoretical computer science, machine learning, and neuroscience. I wish to pursue graduate studies in computer science but I fear I might not be able to since I haven't and won't be allowed to take any computer science courses for the rest of my undergraduate years. My curriculum is made up of the traditional pure and applied mathematics courses (analysis, algebra, topology, differential equations, vectors and tensors, probability, etc.) without emphasis on computer science.
My question is, would I be able to apply, generally, for graduate studies in computer science with my degree only as a starting point? I am also taking classical courses in computer science (data structures, algorithms, etc.) online (e.g. Coursera) and I'm very good in programming. Would these add to my chances of being considered for the admissions? In all, if there are any ideas of what I could do, I'd love to hear it.