The first requirement for entering this field is familiarity with computers. Many young computer mathematicians at the B.S. or M.S. level are in fact hired as computer programmers. Those with a good mathematics background can quickly work themselves up beyond this level. Studies in numerical analysis and algorithms can be especially useful in this regard. There is a wealth of genuine mathematical problems in computer programming involving logic, combinatorics, number theory, and algebra.
Computers are expensive to operate and there is a premium on efficient usage.
Most users of computers do not understand the non-commutativity of finite arithmetic, or the elementary logic of algorithms, or how to estimate errors in approximations. They routinely use the most available computer program, regardless of its real applicability. Someone who can understand poorly-worded problems and translate them into efficient algorithms becomes valuable. All the statistics indicate that high school teaching is a field that is overcrowded at present. This is, however, not true for mathematics.