Proving Convergence of Sequence an: limn→∞an

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    Convergence Sequence
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Discussion Overview

The discussion centers around proving the convergence of the sequence defined by \( a_n = \frac{(2n)!}{(n!)^2} \cdot 4^{-n} \) as \( n \) approaches infinity. Participants are tasked with finding the limit of this sequence.

Discussion Character

  • Technical explanation, Mathematical reasoning

Main Points Raised

  • One participant presents the sequence \( a_n = \frac{(2n)!}{(n!)^2} \cdot 4^{-n} \) and requests proof of its convergence.
  • Another participant clarifies the notation used in the sequence, indicating it represents "2n choose n."
  • A further contribution suggests that the term \( \frac{(2n)!}{(n!)^2} \) is a polynomial in \( n \), while \( 4^{-n} \) is exponential and decreases to 0 faster than any polynomial increases, implying a potential convergence to 0.

Areas of Agreement / Disagreement

Participants have not reached a consensus on the limit of the sequence or the method of proof. Multiple viewpoints regarding the behavior of the sequence as \( n \) approaches infinity remain present.

Contextual Notes

The discussion does not clarify the assumptions regarding the definitions of convergence or the specific mathematical tools to be used in the proof.

e.gedge
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Let an= ( 2n ) 4-n, for all n greater than or equal to 1
( n )

Prove that sequence an converges to a limit, and find limn->infinityan.
 
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that was supposed to be

( 2n )
( n )
 
As in, 2n choose n
 
[itex]_{2n}C_n[/itex] is a polynomial in n and 4-n, being exponential, goes to 0 faster than any polynomial goes to infinity.
 

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