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The Prime Number Theorem is one of the most famous theorem in mathematics.  It states that the number of primes not exceeding n is asymptotic to n/log(n), where log(n) is the logarithm of (n) to the base e.   
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The Prime Number Theorem is one of the most famous theorem in mathematics.  It states that the number of primes not exceeding n is asymptotic to <math>\frac{n}{\log(n)}</math>, where log(n) is the logarithm of (n) to the base e.   
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The number of primes not exceeding n is commonly written as pi(n), and an asymptotic relationship between a(n) and b(n) is commonly designated as a(n)~b(n).  (This does not mean that a(n)-b(n) is small as n increases.  It means the ratio of a(n) to b(n) approaches one as n increases.)
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The number of primes not exceeding n is commonly written as <math>\pi(n)</math>, and an asymptotic relationship between a(n) and b(n) is commonly designated as a(n)~b(n).  (This does not mean that a(n)-b(n) is small as n increases.  It means the ratio of a(n) to b(n) approaches one as n increases.)
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The Prime Number Theorem thus states that pi(n) ~ n/log(n) .
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The Prime Number Theorem thus states that <math> \pi(n) </math>~<math> n/ \log(n)</math> .
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In other words, the limit (as n approaches infinity) of the ratio of pi(n) to n/log(n) is one.  Put a third way, n/log(n) is a good approximation for pi(n).
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In other words, the limit (as n approaches infinity) of the ratio of pi(n) to n/log(n) is one.  Put a third way, n/log(n) is a good approximation for <math>\pi(n)</math>.
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== Equivalent Statements ==
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[[Gauus]] conjectured the equivalent statement that <math>\pi(x)</math> was asymptotic to <math>\mbox{Li}(x)</math> defined as:
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<math> \mbox{Li}(x) = \int_2^x \frac{dt}{\ln t}</math>.
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In fact, for large x this turns out to be a better approximation than <math>\pi(x)</math>.
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