Decreasing
Definition
We say a sequence of real numbers is decreasing if for all we have .
Difference between decreasing and nonincreasing
Decreasing -
Nonincreasing -
In a decreasing sequence we cannot have 2 same numbers, but in a nonincreasing sequence we can.
Example
For example, the sequence is decreasing as it satisfies the rule above. On the other hand, the sequence is not decreasing since .