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1 vote
Given the sequence an defined recursively below, find a4.
a1a2an=1=4=2an−1+an−2

User Themink
by
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1 Answer

2 votes

Answer:


a_4=22

Explanation:

Maybe you have ...


a_1=1\\a_2=4\\a_n=2a_(n-1)+a_(n-2)

Then ...


a_3=2\cdot 4+1=9\\\\a_4=2\cdot 9+4=22

User Alaa Gamal
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