Question

What is the recursive formula for -7,-1,5,11

Answer 1

-1 - (-7) = 6
5 - (-1) = 6
11 - 5 = 6
The common difference is 6.
If you add 6 to a term, you get the next term.

$a_0 = -7$

$a_n = a_{n - 1} + 6$