Write the formula for the general term of the sequence. Assume the first term of the sequence corresponds to n = 1.
2, 8, 18, 32, 50,...
The first thing we'll do for the sequence is make a table to help us see the relationship between n and an.
These numbers are all even, so we'll guess that they're 2 multiplied by something.
The general term is an = 2n2.