What math would you mean? Calculus? More on the "building the theory" or "being able to do differential equations" Algebra? Linear? Group-theory? Discrete ma

What math would you mean? Calculus? More on the "building the theory" or "being able to do differential equations" Algebra? Linear? Group-theory? Discrete math? Logic? Proofs within logic systems? Completness theorem? Graph Theory? There is lots of different parts of math that would be suited to different kinds of projects :-)