SOLUTION: to find the first 3 terms of the Recursively defined sequence: a1=5 , an=2a n-1 for the answer I got 5,10,20... is this correct?

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Question 149448: to find the first 3 terms of the Recursively defined sequence:
a1=5 , an=2a n-1
for the answer I got 5,10,20...
is this correct?
Found 2 solutions by Fombitz, jim_thompson5910:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
a%5B1%5D=5
a%5B2%5D=2%2Aa%5B1%5D=2%2A5=10
a%5B3%5D=2%2Aa%5B2%5D=2%2A10=20
a%5B4%5D=2%2Aa%5B3%5D=2%2A20=40
Yes, you are correct.

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
a%5B1%5D=5

Since a%5Bn%5D=2a%5Bn-1%5D, this means that...

when n=2, then

a%5B2%5D=2a%5B2-1%5D=2a%5B1%5D=2%285%29=10


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when n=3, then

a%5B3%5D=2a%5B3-1%5D=2a%5B2%5D=2%2810%29=20


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So the sequence is 5,10,20. So you are correct.