Answer: The answer is -30 - 45 k
Step-by-step explanation:
You can see how the difference between two consecutive terms is constantly increasing:




So, for the next terms we'll have to add +9, +11, +13 and so on.
Also, note that
is obtained by adding the 2nd odd number to
,
is obtained by adding the 3rd odd number to
, and so on.
So, the recursive formula is

For the explicit formula, recall that the sum of the first n odd numbers is n squared. Taking into account the fact that we're not starting from 1, we have

6(2(5)-4)= 6(10-4)= 6(6)=36 so your answer is 36
You write a number in exponents like this 1 [(9+8)-5]