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Erdős–Kac Theorem
In number theory, the Erdős–Kac theorem, named after Paul Erdős and Mark Kac, and also known as the fundamental theorem of probabilistic number theory, states that if ''ω''(''n'') is the number of distinct prime factors of ''n'', then, loosely speaking, the probability distribution of : \frac is the standard normal distribution. (\omega(n) is sequence OEIS:A001221, A001221 in the On-Line Encyclopedia of Integer Sequences, OEIS.) This is an extension of the Hardy–Ramanujan theorem, which states that the Normal order of an arithmetic function, normal order of ''ω''(''n'') is log log ''n'' with a typical error of size \sqrt. Precise statement For any fixed ''a'' < ''b'', : where is the normal (or "Gaussian") distribution, defined as : More generally, if ''f''(''n'') is a strongly additive function ( |
Number Theory
Number theory is a branch of pure mathematics devoted primarily to the study of the integers and arithmetic functions. Number theorists study prime numbers as well as the properties of mathematical objects constructed from integers (for example, rational numbers), or defined as generalizations of the integers (for example, algebraic integers). Integers can be considered either in themselves or as solutions to equations (Diophantine geometry). Questions in number theory can often be understood through the study of Complex analysis, analytical objects, such as the Riemann zeta function, that encode properties of the integers, primes or other number-theoretic objects in some fashion (analytic number theory). One may also study real numbers in relation to rational numbers, as for instance how irrational numbers can be approximated by fractions (Diophantine approximation). Number theory is one of the oldest branches of mathematics alongside geometry. One quirk of number theory is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
