Number patterns in algebra

In Mr Madge's maths class we are studying algebra. We are currently learning about the following:

Number Patterns in Algebra:

Numeric patterns in algebra are patterns made from numbers.
The numbers can be in a list. Any math operation (addition, subtraction, multiplication, or division) can be used to make the pattern
Many of the patterns in algebra you see will use addition. The same number will be added to each number in the list to make the next number in the list.
Example
       2, 4, 6, 8, 10, 12, 14…
The pattern in algebra is to add 2 every time. The next number is 16, then 18.

Examples for Number Patterns in Algebra:

Example 1:

            2,5,8,11,14,17…

Solution:

The pattern in algebra is to add 3 every time. The next number is 20, then 23.

Example 2:

            1,3,5,6,9,11,13,15,…

Solution:

Can you guess what the solution is

(Source) tutor vista