What is the limit of the sequence (Xn) = (n!)^(1/n)?

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The limit of the sequence (Xn) = (n!)^(1/n) is being analyzed, with a consensus that it diverges as n approaches infinity. To demonstrate this, using logarithms and Stirling's formula is suggested as an effective method. An elementary proof involves taking the logarithm, leading to the expression (1/n)log[n]!, which can be simplified to the sum of logarithms divided by n. By setting bounds for different ranges of n, it is shown that the sums diverge, reinforcing the conclusion. The discussion emphasizes the divergence of the sequence as n increases.
steviet
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I'm working on the limit of the sequence
(Xn) = (n!)^(1/n)
Pretty sure it diverges as n goes to infinity,
but unsure how to show it.
Any hint would ge greatly appreciated.
 
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Your instincts are good. Take a log and use Stirling's formula. That's one way.
 
an elemetary proof is to take log so you get (1/n)log[n]! then you get [log1+Log2+log3...logn]/n

set bounds for 1<n<11 sum truncate terms
you get sum between 0 and 1

for 11<n<101 get sum between 10 and 20

you can see how this diverges
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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