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problem with primes in intervals
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rex88
P versus NP
P versus NP

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#1
problem with primes in intervals

is the following statement true ?

for every integer n>0 there is a prime between 10^n and 10^n+10^{n-1}+1

PostPosted: Mon Oct 19, 2009 5:58 am  Back to top 
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mavropnevma
Yang-Mills Theory
Yang-Mills Theory


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#2
A generalization of Bertrand's postulate states that

For any c > 0 there exists positive integer N_c such that for any integer n\geq N_c
there exists at least a prime between n and (1 + c)n.


The problem is that that N_c may be quite large ...

For your case, since 10^n + 10^{n - 1} + 1 > (1 + 1/10)10^n, we can take c = 1/10.

Also see http://en.wikipedia.org/wiki/Bertrand%27s_postulate

EDIT. In reply to the post following: NO (just rough asymptotic value).
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Last edited by mavropnevma on Mon Oct 19, 2009 12:43 pm; edited 1 time in total 
PostPosted: Mon Oct 19, 2009 7:53 am  Back to top 
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rex88
P versus NP
P versus NP

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#3
thanks

is there any method to effectively find this number N_c for fixed c ?

PostPosted: Mon Oct 19, 2009 12:28 pm  Back to top 
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