The infimum limit, also called the limit inferior or lower limit, of a sequence of real numbers ,
written
and pronounced 'lim-inf,' is the limit of
as . Note that by definition,
is nondecreasing, and so either has
a limit or tends to
.
For example, suppose
,
then for
odd,
,
and for
even,
.
Another example is
,
in which case
is a constant sequence
.
When ,
the sequence converges to the real number
Otherwise, the sequence does not converge.