Smallest K in N with 32 Divisors

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Discussion Overview

The discussion revolves around finding the smallest integer \( K \) in a set \( N \) such that \( K \) has exactly 32 divisors. The context includes mathematical reasoning related to the properties of divisors and prime factorization.

Discussion Character

  • Mathematical reasoning

Main Points Raised

  • One participant proposes to find \( K \) such that \( K = P_1 P_2 \ldots P_n \), where \( P_i \) are distinct primes, and the number of divisors of \( K \) equals 32.
  • Another participant provides a hint related to the problem but does not elaborate on the solution.
  • A third participant confirms the interpretation that \( P_1, P_2, \ldots \) are intended to be prime numbers based on the definition provided.
  • A later reply expresses approval of the confirmation regarding the primes, indicating engagement with the discussion.

Areas of Agreement / Disagreement

Participants generally agree on the interpretation of the variables and the nature of the problem, but the specific solution or method to find \( K \) remains unresolved.

Contextual Notes

There are no explicit assumptions or limitations noted, but the problem's dependence on the properties of prime factorization and divisor counting is implicit.

mathworker
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Let $$N$$ be a set such that $$K \text{ belongs to }N$$ iff $$K=P_1P_2...P_n$$ such that $$P_i=P_j \text{ iff }i=j$$ find a smallest K in N such that number of divisors of K=32
edit:sorry for using same variable in two places.k is changed to n
 
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Re: divisors problem

Hint:
though backstabing humans is not allowed backstabing problems is allowed.
To find the smallest begin from the smallest
 
Re: divisors problem

Just to check, $P_1, P_2, \cdots$ are meant to be prime, right? (I think so because of the $P_i = P_j ~ ~ \iff ~ ~ i = j$ part).

If so, then $N$ basically contains all integers which no prime divides twice, i.e:

$K = p_1^{\alpha_1} p_2^{\alpha_2} \cdots p_n^{\alpha_n} \in N ~ ~ \implies ~ ~ \alpha_1 = \alpha_2 = \cdots = \alpha_n = 1$

Then from this prime power factorization it follows that the number of divisors of $K$ is:

$$d(K) = \prod \left ( \alpha_i + 1 \right ) = 2^n ~ ~ (\text{since all} ~ \alpha_i = 1)$$

And $d(K) = 32$ when $n = 5$. So we are looking for the smallest $K$ which has five distinct prime factors. Trivially, the solution is:

$$p_5 \# = 2 \cdot 3 \cdot 5 \cdot 7 \cdot 11 = 2310$$
 
Re: divisors problem

Bacterius+ (Clapping)you got it(flower)
 

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