-2. - 8, - 18, - 32, - 50, find the rules Please be more specific, Please be more specific. What's the 20th number, how to list the formula, and what are the symbols of *, ^

-2. - 8, - 18, - 32, - 50, find the rules Please be more specific, Please be more specific. What's the 20th number, how to list the formula, and what are the symbols of *, ^

AHA ~ I know~
The order is - 2 times the square of 1, - 2 times the square of 2, and - 2 times the square of 3
So 20 is - 2 times the square of 20, is - 800!