If you have a sequence with a constant first common difference, it can be defined using a linear equation. The following formula can be used to find any nth term in the sequence.
Where:
a is the first term in the sequence
d is the common difference between the terms
When you cannot find a constant first common difference, look at the second differences. If that second difference is constant, you can define the sequence using a quadratic equation. The following formula can be used to find any term in the sequence.
Where:
a is the first term in the sequence
d is the difference between the first and the second term
c is the common second difference you found.
