SOLUTION: Find a8 if a1=-21, an=an-1-3; for n=2,3,4.... Please help me solve this one. I don't know how to do it.

SOLUTION: Find a8 if a1=-21, an=an-1-3; for n=2,3,4.... Please help me solve this one. I don't know how to do it.

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Question 38031: Find a8 if a1=-21, an=an-1-3; for n=2,3,4.... Please help me solve this one. I don't know how to do it.
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!

Find a8 if a1=-21, an=an-1-3
You have a garble in your posting
an cannot be an-1-3 as you have indicated.
Cheers,
Stan H.
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