SOLUTION: Can I know what particular equation can I use to find the nth term of this sequence? 5,12,31,68,129

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Question 1061052: Can I know what particular equation can I use to find the nth term of this sequence? 5,12,31,68,129
Answer by Edwin McCravy(20065) About Me  (Show Source):
You can put this solution on YOUR website!

5,12,31,68,129

Let's get a related sequence with the first term 1, 
by subtracting 4 from each term

1,8,27,64,125

Hey! Those are the cubes:

13,23,33,43,53

So we just add 4 to n3, and we have the general term:

a%5Bn%5D%22%22=%22%22n%5E3%2B4

Edwin