Jacques Inaudi, Italian calculating prodigy (died 1950)

Giacomo Inaudi, also known as Jacques Inaudi in France, was an Italian calculating prodigy.

Mental calculation consists of arithmetical calculations made by the mind, within the brain, with no help from any supplies or devices such as a calculator. People may use mental calculation when computing tools are not available, when it is faster than other means of calculation, or even in a competitive context. Mental calculation often involves the use of specific techniques devised for specific types of problems. Many of these techniques take advantage of or rely on the decimal numeral system.

October 13 is the 286th day of the year in the Gregorian calendar; 79 days remain until the end of the year.