A wide variety of large numbers crop up in mathematics. Some are contrived, but some actually arise in proofs. Often, it is possible to prove existence theorems by deriving some potentially huge upper limit which is frequently greatly reduced in subsequent versions (e.g., Graham's number, Kolmogorov-Arnold-Moser theorem, Mertens conjecture, Skewes number, Wang's conjecture).Large decimal numbers beginning with are named according to two mutually conflicting nomenclatures: the American system (in which the prefix stands for in ) and the British system (in which the prefix stands for in ). The British names for billion, trillion, etc. originate from the late 15th century when the French physician and mathematician Nicolas Chuquet (1445-1488) used the Latin prefixes to denote successive powers of one million () and the suffix "-llion" to refer one million (Rowlett). In more recent years, the "American" system..
In the American system, one billion equals . In the French and German systems, one billion equals .In recent years, the "American" system has become common in both the United States and Britain. In the words of The Chicago Manual of Style (2003), "The American definitions are gaining acceptance, but writers need to remember the historical geographic distinctions." This use of a common meaning for "billion" constitutes a fortunate development for standardization of terminology, albeit a somewhat regrettable development from the point of view that the British convention for representing large numbers is simpler and more logical than the American one.