[see also: arise, appear, emerge, happen, result
The only case requiring further analysis occurs when f=0.
Both cases can occur.
All inputs of size n are equally likely to occur.
Every nonincreasing function occurs as the rearrangement of some C(P) function.
Equality occurs in (9) if......
Where we could, we have chosen these examples from naturally occurring mathematical structures. [Note the double r in occurring.]