Very simple question about limit superior (or upper limit)

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SUMMARY

The discussion centers on the limit superior of the sequence Tn defined as Tn = (1 + (1/n))^n and its relationship to the mathematical constant e (approximately 2.71). The participants clarify that while Tn is bounded above by e, the limit superior of Tn does not necessarily imply that lim sup Tn < e. It is established that lim sup Sn = e, which leads to the conclusion that lim sup Tn ≤ e, but not lim sup Tn < e.

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Homework Statement



If Sn =1/0! + 1/1! + 1/2! +... 1/n! , Tn=(1+(1/n))^n, then lim sup Tn ≤ e? (e=2.71...)

Homework Equations



1. e= Ʃ(1/n!)
2. If Sn≤Tn for n≥N, then lim sup Sn ≤ lim sup Tn

The Attempt at a Solution



By binomial theorem,
Tn= 1 + 1 + 1/(2!)(1-1/n) + 1/(3!)(1-1/n)(1-2/n) + ... + 1/n!
Hence Tn ≤ Sn< e,
lim sup Tn ≤ lim sup Sn< e

∴ lim sup Tn< e

But I do not get lim sup Tn ≤ e

What did i do wrong?
 
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1. If you show that limsup Tn < e, then it follows that limsup Tn ≤ e. It turns out that it is not true that limsup Tn < e (so you did mess up in coming to that conclusion), but this conclusion does not contradict the claim that Tn ≤ e.
2. If Tn ≤ Sn < e, then we can conclude that limsup Tn ≤ limsup Sn ≤ e. We cannot, however, conclude that limsup Sn < e based on this information; in fact, limsup Sn = e.
 

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