That’s a pretty important distinction. If someone in the 1800s invented a mechanical calculator that could do this operation in a single crank, I don’t think anyone would upset about that patent.
Back before software patents were a thing, the "math" was not patentable. Eliminating software patents will be a return to the previous status quo.
The only thing this patent covers is the physical circuit implementation, not the math.
The claims in that patent are not limited to a physical circuit implementation.
The description includes a circuit diagram as one possible embodiment of the claimed invention, but the patent covers any implementation (and the description indicates it was intended to cover instructions running on general purpose processors).