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Find a recursive formula for the following sequence:4, 11, 25, 53, 109, ...

User Haresh Samnani
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1 Answer

17 votes
17 votes

Notice the following pattern in the given sequence:


\begin{gathered} 11=4\cdot2\text{ +3,} \\ 25=11\cdot2+3, \\ 53=25\cdot2+3, \\ 109=53\cdot2+3. \end{gathered}

Therefore, the n-term of the sequence has the following form:


a_n=a_{n-1\text{ }}+3.

Answer:


a_n=a_{n-1\text{ }}+3.

User Jnbdz
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