Placing Balls in Numbered and Unnumbered Boxes: Infinite Possibilities

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Discussion Overview

The discussion revolves around a combinatorial problem involving placing an infinite number of balls into a set of numbered and unnumbered boxes, each with a specified capacity. Participants explore various approaches to determine the number of ways to fill the boxes under different conditions.

Discussion Character

  • Exploratory
  • Mathematical reasoning
  • Debate/contested

Main Points Raised

  • One participant suggests that the number of ways to fill the boxes with infinite balls in numbered boxes might be $n^n$.
  • Another participant questions the reasoning behind the $n^n$ claim, considering the capacity of each box.
  • There is a discussion about the implications of having infinite identical balls versus unique balls, with one participant noting that if the balls are unique, there would be infinite ways to fill the boxes.
  • Participants explore the scenario of filling a single box with a capacity of $n=3$ balls, discussing the possible configurations (0, 1, 2, or 3 balls).
  • One participant concludes that for one box with capacity $n$, there are $n+1$ ways to fill it, leading to the generalization that $n$ boxes have $(n+1)^n$ ways to be filled.
  • A later contribution interprets the unnumbered box scenario as a question about forming unique sets from distinct symbols, providing a recursive formula for the number of combinations.

Areas of Agreement / Disagreement

Participants express differing views on the initial claim of $n^n$ and the implications of the balls being identical or unique. The discussion remains unresolved regarding the exact number of configurations for both numbered and unnumbered boxes.

Contextual Notes

Assumptions about the nature of the balls (identical vs. unique) and the interpretation of the problem (numbered vs. unnumbered boxes) are critical to the discussion but remain unresolved.

evinda
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Hey! (Giggle)

I am given this exercise:
If we have a pile of infinite balls and $n$ numbered boxes with a capacity of $n$ balls each one,with how many ways can we place some balls in the boxes?Answer the same question,if the boxes are not numbered.

Could you give me a hint what to do?? :rolleyes: (Blush)
 
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Is it maybe $n^n$ ?? Or am I wrong? :confused:
 
evinda said:
Hey! (Giggle)

I am given this exercise:
If we have a pile of infinite balls and $n$ numbered boxes with a capacity of $n$ balls each one,with how many ways can we place some balls in the boxes?Answer the same question,if the boxes are not numbered.

Could you give me a hint what to do?? :rolleyes: (Blush)

evinda said:
Is it maybe $n^n$ ?? Or am I wrong? :confused:

Hi! (Smirk)

How did you get $n^n$?
 
I like Serena said:
Hi! (Smirk)

How did you get $n^n$?

I thought it,because of the fact that there are $n$ numbered boxes,and at each one we can put $n$ balls..Is it wrong?? :confused: (Thinking)
 
evinda said:
I thought it,because of the fact that there are $n$ numbered boxes,and at each one we can put $n$ balls..Is it wrong?? :confused: (Thinking)

Let's start with 1 box that can contain $n=3$ balls.
What are the possibilities to fill it? (Wondering)
 
I like Serena said:
Let's start with 1 box that can contain $n=3$ balls.
What are the possibilities to fill it? (Wondering)

With infinite balls,or not?? :confused:
 
evinda said:
With infinite balls,or not?? :confused:

Yes. (Wasntme)
And I guess we'll have to assume those infinite balls are identical, or the problem becomes a bit non-sensical otherwise.
 
I like Serena said:
Yes. (Wasntme)
And I guess we'll have to assume those infinite balls are identical, or the problem becomes a bit non-sensical otherwise.

So,are there infinite ways?? :eek: Or is there an other formula,that expresses it?? (Thinking)(Thinking)
 
evinda said:
So,are there infinite ways?? :eek: Or is there an other formula,that expresses it?? (Thinking)(Thinking)

If the infinite balls are unique, there would indeed be infinite ways.
That is why I am assuming that they can not be distinguished from each other. (Wink)

So 1 box with capacity 3 could for instance contains 3 balls.
What are the other possibilities?
How many are those?
 
  • #10
I like Serena said:
If the infinite balls are unique, there would indeed be infinite ways.
That is why I am assuming that they can not be distinguished from each other. (Wink)

So 1 box with capacity 3 could for instance contains 3 balls.
What are the other possibilities?
How many are those?

So,is it also possible that 1 box contains also $2$, $1$ or $0$ balls?
But how can I find then the number of ways we can place some balls in the boxes?? (Thinking)
 
  • #11
evinda said:
So,is it also possible that 1 box contains also $2$, $1$ or $0$ balls?
But how can I find then the number of ways we can place some balls in the boxes?? (Thinking)

Now I am going to assume the box does not have specific places for the balls, but that it just contain a number of balls.

So for 1 box with capacity $n=3$ we have $4$ ways to fill it... (Thinking)
 
  • #12
I like Serena said:
Now I am going to assume the box does not have specific places for the balls, but that the just contain a number of balls.

So for 1 box with capacity $n=3$ we have $4$ ways to fill it... (Thinking)

So,one box with capacity $n$ has $n+1$ ways to be filled.So,in general, $n$ boxes have $(n+1)^n$ ways to be filled,right?? :rolleyes:
 
  • #13
evinda said:
So,one box with capacity $n$ has $n+1$ ways to be filled.So,in general, $n$ boxes have $(n+1)^n$ ways to be filled,right?? :rolleyes:

Right! (Cool)
 
  • #14
I like Serena said:
Right! (Cool)

Great!Thank you very much! (Clapping)
 
  • #15
evinda said:
Hey! (Giggle)

I am given this exercise:
If we have a pile of infinite balls and $n$ numbered boxes with a capacity of $n$ balls each one,with how many ways can we place some balls in the boxes?Answer the same question,if the boxes are not numbered.

For the second question, I interpret this as being equivalent to asking: "how many unique sets of n objects can be formed by selecting zero or more of each of n distinct symbols".

So, for n=2 we have R(2)=3: aa, ab, bb

and in general, for n>3, we have:
\[R(n)=\sum_{m=1}^{n}mS(n-m+1)=R(n-1)+\sum_{m=1}^{n}S(m)\]

where \[S(n)=\sum_{k=1}^{n}k=\frac{n(n+1)}{2}\]
 
Last edited:

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