For an arithmetic sequence, the nth term is calculated using the formula xn (+ or -)x (x is a number
Example- Here is a sequence of numbers:
4, 10, 16, 22, 28
to find the nth term you need to work out the difference- so 10-4=6 this is similar to the 6 time table
6, 12, 18, 24, 30
so the nth term would be 6n-2
hope this helps