Online Course Discussion Forum

Question on II-A

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Question on II-A
by Kevin Song - Saturday, January 30, 2021, 7:27 AM

How would you write a bijection (7.25)?

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Re: Question on II-A
by Charles Zhang - Saturday, January 30, 2021, 2:20 PM

One-to-one, with every one of them used up.  (Hint: Look at 7.4b in lecture.)

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Re: Question on II-A
by Areteem Professor - Monday, February 1, 2021, 2:46 PM
You need to associate each way to arrange the $n$ identical balls into the $k$ boxes to a solution of the equation $a_1 + \cdots + a_k = n$, and vice versa.