SOLUTION: What is the nth term for the following sequence: 2, 8, 18, 32, 50, 72, ...

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Question 1182230: What is the nth term for the following sequence:
2, 8, 18, 32, 50, 72, ...
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
2, 8, 18, 32, 50, 72, ...

Notice that they can all by divided by 2

1, 4, 9, 16, 25, 36, ...

That is the sequence of squares:

12, 22, 32, 42, 52, 62, ...

So the original sequence is twice the sequence of squares, whose nth term
is n2, so the answer is

a%5Bn%5D%22%22=%22%222n%5E2

Edwin