[Math] Convergence of Monotone sequences? example

convergence-divergenceexamples-counterexamplesreal-analysissequences-and-series

An example of an unbounded increasing sequence that satisfies the assumptions of the convergence of monotone sequences…?

According to the convergence of monotone sequences if a sequences is monotonic and bounded then it converges to some $L$.

I think $S(n)=n+1$ since it's increasing and it's unbounded
correct?

Best Answer

Your example $a_n = n$ satisfies that it is monotone but not bounded, and is therefore not necessarily convergent. For an example that is bounded but not monotone, just take the sequence $-1, 1, -1, 1, \ldots$. Any convergent sequence must be bounded. But not every convergent sequence must be monotone. Just take $a_n = (-1)^n/n$.

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