Number of unique ways of stacking n blocks

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Discussion Overview

The discussion revolves around the problem of determining the number of unique ways to stack n blocks, where the order of stacking does not matter. This includes exploring connections to abstract algebra and integer partitions, as well as assessing the feasibility of solving the problem with a basic understanding of combinatorics.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Main Points Raised

  • One participant questions the solvability of the problem and its feasibility for someone with a decent knowledge of combinatorics.
  • Another participant suggests that the problem is equivalent to finding the number of partitions of n, indicating a potential method for exploration.
  • The original poster connects the problem to a theorem in abstract algebra regarding finite abelian groups and cyclic groups, proposing a relationship between stacking blocks and group structures.
  • The original poster provides an alternative perspective by framing the problem in terms of grouping star symbols, emphasizing that order is irrelevant.

Areas of Agreement / Disagreement

Participants generally agree on the connection between the stacking problem and integer partitions, but the discussion remains open regarding the methods and approaches to solving the problem.

Contextual Notes

The discussion does not resolve the mathematical steps or assumptions involved in determining the number of unique arrangements, nor does it clarify the dependencies on definitions related to partitions.

hello95
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Hello,

I was wondering if this problem is one that is solvable, and if so, if I would be able to solve it in a reasonable amount of time.

Basically, say you have n blocks. You can arrange this blocks in stacks, so for example, if you had 3 blocks, you could make a stack of 2, and then add a stack of 1. The question is, for these n blocks, how many unique ways are there of arranging them in stacks (the order is irrelevant). I got the idea from a theorem in abstract algebra, which says that a finite abelian group is isomorphic to the direct product of cyclic groups with orders equal to some integral power of a prime. Since such a direct product would be isomorphic to a cyclic group equal to the product of all of the prime power orders, then I could find a way to represent all of the possible forms of a cyclic group of order (2^7)(5^2) by simply taking the number of ways of stacking 7 blocks and multiplying it by the number of ways of stacking 2 blocks.

Another way of looking at the problem would be, if you have n star symbols (*), how many ways would there be of grouping certain numbers of those stars together so that the sum of all of the elements in all of the groupings equaled n:

(*)(*)(*)(*), (**)(**), (*)(***), (****)

Once again, order is irrelevant.

If you know the answer, please do not post it. Ultimately I just want to know if this problem is feasible for someone with a decent knowledge (but my no means expansive) of combinatorics to attempt.

Thank you.
 
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If any further explanation is needed, please let me know.
 
If order is irrelevant, this strikes me as being equivalent to asking for the number of partitions of n. A google search for "integer partitions" should reveal plenty of information.
 
Thank you! that's exactly what I was looking for.
 

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