Monotonic 0<an<1 for all n and no two terms are the same

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Homework Statement



Give an example of a sequence {an}, satisfying the following:
{an} is monotonic
0<an<1 for all n and no two terms are the same
lim(n→∞) an = 1/2

Homework Equations


what is monotonic


The Attempt at a Solution


1/(2√n)
n/(2n-1)
1/2^n

just been trying genearal sequences but none of them work
 
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Does this one work?

a_n = \frac{1}{2 } + \frac{1}{n}\ \forall n&gt;2
 


what would be the first term?
 


Oh, c'mon! Use any two numbers less than 1/2 for a1 and a2.
 


monotonic refers to how it increases. monotonic increasing means each term is greater than or equal to the term before it. monotonic decreasing means each term is less than or equal to the term before it. if it just says monotonic, either situation will work.
 


dirk_mec1 said:
Does this one work?

a_n = \frac{1}{2 } + \frac{1}{n}\ \forall n&gt;2

For all n
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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