from
The Free On-line Dictionary of Computing (8 July 2008)
prime number theorem
<mathematics> The number of {prime numbers} less than x is
about x/log(x). Here "is about" means that the ratio of the
two things tends to 1 as x tends to infinity. This was first
conjectured by {Gauss} in the early 19th century, and was
proved (independently) by Hadamard and de la Vall'ee Poussin
in 1896. Their proofs relied on {complex analysis}, but Erdös
and Selberg later found an "elementary" proof.
(1995-04-10)