Binary code The modern binary number system, the basis for binary code, was invented by Gottfried Leibniz in 1689 and appears in his article "Explication de l'Arithmétique Binaire". The full title is translated into English as the "Explanation of the binary arithmetic", which uses only the characters 1 and 0, with some remarks on its usefulness, and on the light it throws on the ancient Chinese figures of Fu Xi." (1703). Leibniz's system uses 0 and 1, like the modern binary numeral system. Leibniz encountered the "I Ching" through French Jesuit Joachim Bouvet and noted with fascination how its hexagrams correspond to
Combinatorial number system of a set "S" is a subset of "S" with "k" (distinct) elements. The main purpose of the combinatorial number system is to provide a representation, each by a single number, of all formula_1 possible "k"-combinations of a set "S" of "n" elements. Choosing, for any "n", } as such a set, it can be arranged that the representation of a given "k"-combination "C" is independent of the value of "n" (although "n" must of course be sufficiently large); in other words considering "C" as a subset of a larger set by increasing "n" will not change the number that