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Limit of a Sequence

A sequence of elements $ f_1,f_2,\dots$ in a vector space, or more generally in a metric space, is said to converge to the element $ f$ if

$\displaystyle \lim_{n\to\infty} f_n=f.
$

The element $ f$ is called the limit of the sequence $ \{ f_n\}$ . The meaning of this is that the distance

$\displaystyle d(f_n,f)=\Vert f_n-f\Vert
$

between $ f$ and $ f_n$ can be made arbitrarily small by making $ n$ sufficiently large. To summarize, a convergent sequence is one which converges to a limit.

Side Comment: It is easy to show that this limit is unique, a property which applies to all metric spaces.



Ulrich Gerlach 2007-04-05