SOLUTION: What is the formula for the sequence 5,5,35,65,275. . .

Question 1014011: What is the formula for the sequence 5,5,35,65,275. . .
Answer by Edwin McCravy(20066) (Show Source): You can put this solution on YOUR website!

First we'll try a sum of nth powers with the first two terms:
If that doesn't work, we'll try the difference of nth powers

No good. Comes out with imaginary values for x and y
So we try a difference of powers for the first two terms:

So the formula we get from the first two terms,
substituting x=3 and y=-2 in

becomes

But we must check to see if it holds for all the given
numbers in the series:

So it works for all the given terms, so the formula is:

Edwin
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