Exercise 40 Page 576

Next, we type $+(\text{-}7)$ and the expression $\text{Ans}+(\text{-}7)$ appears.

Then, if we press $\boxed{\text{ENTER}}$ once, we can find the second term of the sequence.

Let's first find the $6^{\text{th}}$ term. To do so we will press $\boxed{\text{ENTER}}$ five times in total.

Therefore, the $6^{\text{th}}$ term is $\text{-}33.$ Proceeding in the same way, to find the $8^{\text{th}}$ term we will press $\boxed{\text{ENTER}}$ seven times in total. To find the $20^{\text{th}}$ term we will press $\boxed{\text{ENTER}}$ nineteen times in total. Let's do it!

Thus, the $8^{\text{th}}$ term is $\text{-}47,$ and the $20^{\text{th}}$ term is $\text{-}131.$