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3 consecutive numbers being (nontrivial) powers
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rex88
P versus NP
P versus NP

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#1
3 consecutive numbers being (nontrivial) powers

are there any 3 consecutive numbers being (nontrivial) powers ?

(n is nontrivial power iff there are k,m>1 such that n=k^m)

there are two: 8=2^3 and 9=3^2

PostPosted: Mon Oct 19, 2009 12:37 pm  Back to top 
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mavropnevma
Yang-Mills Theory
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#2
Caaaaaaaaaataaaaaaaaaalaaaaaaaaaan!

Search Catalan's conjecture (now a theorem) on Google.
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PostPosted: Mon Oct 19, 2009 1:29 pm  Back to top 
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ZetaX
Birch & Swinnerton Dyer
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#3
Congratulations for making a trivial problem as hard as Mihailescu's theorem.
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PostPosted: Mon Oct 19, 2009 1:57 pm  Back to top 
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rex88
P versus NP
P versus NP

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#4
mavropnevma wrote:
Caaaaaaaaaataaaaaaaaaalaaaaaaaaaan!

Search Catalan's conjecture (now a theorem) on Google.

I didn't knew it was proved !!!



how to solve it without using Mr Mihailescu's result ?

PostPosted: Mon Oct 19, 2009 2:04 pm  Back to top 
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mavropnevma
Yang-Mills Theory
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#5
My intention was to scorn the futility of such problems, once Catalan's (or equivalently, other strong) theorem has been proved. Is there any interest in asking, for example, to exhibit a 100-long arithmetic progression made of primes only, after Tao's result? (I think the longest known before that was 23-long or whereabouts).

As for the triviality of the problem as stated, I will quote from Sierpinski's 250 problems of number theory (albeit a venerable piece of work)
Quote:
Four consecutive nontrivial powers cannot be, since two of them will be consecutive even numbers, hence one of them is divisible by 2, but not by 4.
A. Makowski has proved that there exist no three consecutive nontrivial powers. The proof of this theorem is hard (some reference follows).

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PostPosted: Mon Oct 19, 2009 2:38 pm  Back to top 
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rex88
P versus NP
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#6
ZetaX wrote:
Congratulations for making a trivial problem as hard as Mihailescu's theorem.
So ... what about this trivial solution ? Very Happy

PostPosted: Wed Oct 21, 2009 2:55 am  Back to top 
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