Good mathematics teaching starts with familiar hands-on examples of concepts and procedures.
But eventually students need to learn that these concepts and procedures are general — that is, that they apply to a wide variety of different situations including ones they have not yet encountered.
In other words, teaching should aim to encourage students to make abstractions and generalisations.
Abstractions
Students should recognise that the 'same' pattern can be found in quite different situations.
For example, many patterns can be described as 'AAB repeated'. This description is an example of an abstraction — a description of a type of pattern rather than any specific pattern.
Generalisations
Students may also find patterns that show general relationships.
For example, students may notice that the numbers in a growing pattern increase by two each time. This is an example of a generalisation — a relationship that is always true.