I was a math + physics major. "Numerical analysis" was one of the math courses, but you could also get CS credit for it. We also used numerical methods in our physics courses. The CS curriculum at the university near my house requires two math courses beyond basic calculus, but does not require differential equations.

I work at a place that has a mid sized engineering department. The people who regularly handle math related programming tasks tend to have degrees in the physical sciences, and coincidentally are older than 50.