If a sequenceis convergent in a metric space
so that as
it must be a Cauchy sequence, so that given
there exists
such that for
The converse is not the case, so a sequence may be Cauchy without being convergent.
Consider the spacewith the absolute value metric. The sequence is defined as follows:
Each termin the sequence to
to n significant figures. This sequence converges to
but
so
does not converge.