MHB Solve Induction Problem: cn <= n log2n

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The discussion revolves around solving an induction problem related to the number of comparisons, cn, made by a student studying a list of n elements. The user is challenged to prove that cn is less than or equal to n log2n for n >= 2, given specific initial conditions and a recursive relation. There is acknowledgment that the problem may be complex and requires careful application of mathematical induction. An attachment is mentioned that likely contains a solution or guidance on the induction process. The overall goal is to clarify the induction method to establish the inequality for the number of comparisons.
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Hey I've been given an equality to solve as a bonus question with a strong hint that a like one would appear on my midterm.
However, I am stumped by it, it appears quite complex to me. Any insight into how to solve this would be greatly appreciated!
I'll try to type it as best I can:

A student is studying a list with n elements. The student determines that the number of comparisons c sub n when the list has n elements satisfies the following relation:

c0 = c1 = 0
c2 = 1
c3 <= 3
cn <= (2cn/2) + (n - 1) if n >= 4

Prove that for any n >= 2 the value cn satisfies the equation cn <= n log2n

I think I have to use induction to solve this but the question appears tricky and weirdly worded. Any help would be awesome, thank you !
 
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Hi,
The attachment answers your question. The induction is just a little tricky. Presumably, this is the number of comparisons in some algorithm for a list of length n.

View attachment 1715
 

Attachments

  • MHBdiscrete2.png
    MHBdiscrete2.png
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There is a nice little variation of the problem. The host says, after you have chosen the door, that you can change your guess, but to sweeten the deal, he says you can choose the two other doors, if you wish. This proposition is a no brainer, however before you are quick enough to accept it, the host opens one of the two doors and it is empty. In this version you really want to change your pick, but at the same time ask yourself is the host impartial and does that change anything. The host...

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