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Number theory equations

  • Thread starter Funky1981
  • Start date
  • #1
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Homework Statement


Solve the following equations positive integers:

(i) a!+b!+c!=d!

(ii) a!+b!=25*c!

(iii)a!=b^2


Homework Equations



For the first two one , i have no idea how to begin . But the third one I may use Bertrand's Postulate some where. Could anyone give me some ideas??
 

Answers and Replies

  • #2
34,303
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Do you have to find all solutions? The first one has a solution that is easy to find, and you can even prove that there are no other solutions. The second one has a solution with small numbers, too, but I'm not sure how to prove (with pen&paper) that there are no other solutions.

But the third one I may use Bertrand's Postulate some where.
That is a good idea.
 

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