Quandaries and Queries
  

 

Joga

Level: 12th grade Teacher

Problem:

What is nth term:

First sequence:
2, 4,7,11, 16, nth term

Second sequence:
4,10, 28, 82, nth term

Hello, I am having a hard time finding the nth term for both of these sequences. Could you please help me. Also could you tell me how you got the answers for both sequences.

Thank you
Joga

 

 

Hi Joga,

Do you see the pattern in the first sequence?

first term 2
second term 2 + 2
third term 4 + 3
fourth term 7 + 4
fifth term 11 + 5

If you call the terms a1, a2, a2,... then this is
a12 a1
a2a1 + 2 a1 + 2
a3a2 + 3 a1 + 2 + 3
a4a3 + 4 a1 + 2 + 3 + 4
a5a4 + 5 a1 + 2 + 3 + 4 + 5
 
 

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