Question

Find the nth-term of the sequence whose first few terms are written out?

Answer 1

Notice that the magnitude of the terms is the squares of the first `n` integers, or `n^2`. Also notice that the sign of the terms alternates.

Thus

`a_n = (-1)^(n - 1) n^2`, where `n ≥ 1`, and `n` is an integer.

Hopefully this helps!