Addition is the most elementary arithmetic operation required of computers. Their invention and development has almost entirely been to do arithmetic extremely fast. I will present the simplest binary adder circuits (ripple carry adder), show some surprising results about carry propagation, develop carry look-ahead circuits for log-time addition, and then talk about redundant number systems and constant time addition and, consequently, log-time multiplication.
I will also present residue number systems that enable constant time addition and multiplication.
It’s all integer math, modulo arithmetic, and some simple logic circuits.