Finding Perfect Squares of n Factored as a^4*b^3*c^7

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Discussion Overview

The discussion revolves around finding the number of perfect square factors of a number n, which is expressed in the form a4*b3*c7, where a, b, and c are distinct prime numbers greater than 2. The conversation includes attempts to clarify the approach to solving the problem and the reasoning behind counting perfect squares.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested, Mathematical reasoning

Main Points Raised

  • One participant seeks assistance on how to start solving the problem of finding perfect square factors of n.
  • Another participant suggests that if a, b, and c are distinct primes, there are specific counts of perfect squares arising from each prime factor: 2 from a, 1 from b, and 3 from c, leading to a question about the combinations of these perfect squares.
  • A different participant challenges the previous claim, asserting that there are actually 3 perfect squares from a, 2 from b, and 4 from c, emphasizing the importance of including the 0th power in the count.
  • This participant also notes that the combinations of the counts must be carefully considered, as not all combinations will yield unique factors.
  • One participant defends their earlier position by stating they intentionally left out the zero power to encourage further thought from the student.

Areas of Agreement / Disagreement

There is disagreement regarding the counts of perfect squares from each prime factor and whether the zero power should be included in the calculations. The discussion remains unresolved as participants present differing viewpoints without reaching consensus.

Contextual Notes

Participants express varying interpretations of how to count perfect squares and the implications of including or excluding the zero power in their calculations. The discussion reflects uncertainty about the correct approach and the definitions of perfect squares in this context.

shravan
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a number n when factorised can be written as a^4*b^3*c^7.find number of perfect square which are factors of n.a,b,c are prime >2.
I have no idea how to start? please help.
 
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If a, b and c are distinct primes then numbers like [itex]a^2[/itex] are perfect squares and factors of n. There are 2 possible perfect squares arising from a, only 1 from b but 3 possibilities from c so the question is how many combinations are possible with those perfect squares?
 
Tide, how dare you miss such easy things? 3 possible perfect squares from a, 2 possible perfect squares from b and 4 possiblities from c of which in total three are same. You have missed the 0th power. Now the answer is 3*2*4. However during the combination of 2, 1 and 3 we won't get 1. Now the answer 3*2*4 is because for each 3 powers of a, there are two possible powers of b and for each of b there are 4 possibilities of c when each square is taken as the product of powers of each primes.
 
vaishakh,

No, I didn't miss the zero power. I had to leave something for the student to think about!
 

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