Limit with n tending to infinity

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SUMMARY

The discussion centers on the asymptotic relationship between functions f(n) and g(n) as n approaches infinity, specifically when the limit of their ratio equals one, denoted as \(\frac{f(n)}{g(n)}=1\). The prime number counting function, \(\pi(n)\), is highlighted as an example, where \(\pi(n) \sim \frac{n}{\ln(n)}\). A critical question raised involves proving the equality \(\frac{\int_0^{n} x^p \, dx}{1^p + 2^p + 3^p + \ldots + n^p} \rightarrow 1\) as n tends to infinity, emphasizing the polynomial nature of the sum of the first p powers.

PREREQUISITES
  • Understanding of asymptotic notation, specifically the notation \(f(n) \sim g(n)\).
  • Familiarity with the prime number counting function, \(\pi(n)\).
  • Basic knowledge of calculus, particularly integration techniques.
  • Concept of polynomial degrees and their behavior as n approaches infinity.
NEXT STEPS
  • Study the properties of asymptotic notation in detail.
  • Explore the behavior of the prime number counting function, \(\pi(n)\), in number theory.
  • Learn techniques for evaluating improper integrals, especially those involving polynomial functions.
  • Investigate the relationship between sums of powers and their corresponding integrals.
USEFUL FOR

Mathematicians, students of number theory, and anyone interested in advanced calculus and asymptotic analysis will benefit from this discussion.

eljose
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let,s suppose that we have the limit with n tending to infinity:
\frac{f(n)}{g(n)}=1 then i suppose that for n tending to infinity we should get:
f(n)\rightarrow{g(n)} or what is the same the function f(n) diverges as g(n) as an special case:
\pi(n)\rightarrow{n/ln(n)} where Pi is the prime number counting function in number theory
 
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eljose said:
let,s suppose that we have the limit with n tending to infinity:
\frac{f(n)}{g(n)}=1 then i suppose that for n tending to infinity we should get:
f(n)\rightarrow{g(n)} or what is the same the function f(n) diverges as g(n) as an special case:
\pi(n)\rightarrow{n/ln(n)} where Pi is the prime number counting function in number theory
What is your question? What you;'ve written doesn't make sense.

Are you attempting to ask: if f and g are asymptotic then does f-g tend to zero? Of course not: we can make two functions that are asymptotic diverge absolutely as fast as you want.
 
Last edited:
As I recall, that \frac{f(n)}{g(n)}=1\mbox{ as }n\rightarrow\infty speaks of the asymptotic relationship between f and g, namely that f(n) \sim g(n) (ref. Asymptotic Notation).
 
My main question is related with proving (if true) the equality

\frac{\int_0^{n}dx(x^p)}{1^p+2^p+3^p+...+n^p}\rightarrow{1}

as n tends to infinity n\rightarrow{\infty}
 
It certainly tends to a constant (for p an integer), as anyone can tell you, since the sum of the first p powers is a poly of degre p+1. Surely you can actually solve it, it's straightforward (especially from someone who has solved the RH amongst other things that snobbish mathematicians wont' acknowledge (you cry wolf and what do you expect?)), at least try simplifying the integral (ie doing it).
 
Last edited:

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