Finding Squares Between Cubes in Elementary Number Theory

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Homework Help Overview

The discussion revolves around a problem in elementary number theory, specifically concerning the existence of squares between cubes of integers. The original poster seeks to demonstrate that for positive integers greater than or equal to 8, there are at least two squares between any two cubes.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants explore the specific case of cubes 8^3 and 9^3, identifying squares within that range. Others question how to generalize this to arbitrary cubes n^3 and (n+1)^3, suggesting a contradiction approach involving squares and cubes.

Discussion Status

The discussion is active, with participants providing specific examples and raising questions about generalization. Some guidance has been offered regarding the contradiction method, but no consensus has been reached on a complete solution.

Contextual Notes

There is a focus on the restriction of integers being greater than or equal to 8, which may influence the reasoning and examples provided. The discussion also hints at the need for a general proof rather than specific instances.

tara123
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Im really good at number theory but how to show this statement has me stumped!

"Show that among the positive integers greater than or equal to 8, between any two cubes there are at least 2 squares"
 
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Can you find 2 squares between n^3 and (n+1)^3?
 
yah if u allow for the restriction of n>=8
if u have 8^3=512 and 9^3=729
then there's 23^2=529 and 24^2=576 both of which are between the cubes..
 
You have found two squares between the two particular cubes 8^3 and 9^3, but what about between two generic cubes n^3 and (n+1)^3, where n is arbitrary (and >1).

You can do it by showing it is not possible to have two cubes between m^2 and (m+2)^2. That is, assume m^2 < n^3 and (n+1)^3 < (m+2)^2 and deduce a contradiction.
 

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