Need help finding the formula (nth) term of the following sequence

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So my friend gave me this sequence

$\frac 32$ $\quad$ $ \frac 54$ $\quad$ $\frac {21}{16}$ $\quad$ $\frac {45}{32}$

Each of these numbers corresponds to n = 2 , n = 4 , n = 6 ... so to even n values , for odd values of n he gave me nothing , it is blank.

  • For the denominators i was planning on using $\frac {2^n}{n}$ but the term 8 is missing from this geometric sequence.

  • For the numerators $ n(n-2)- 3 $ was the plan , however it does not work the first one

I think he might be messing with me , but is there any possible way to find the formula for the nth term of this sequence???

Thank you very much in advance your time and help!

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3
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Consider the products \begin{eqnarray*} \frac{1}{1} ,\frac{3}{2} , \frac{3 \times 5}{3 \times 4} ,\frac{3 \times 5 \times 7}{4 \times 5 \times 6} ,\frac{3 \times 5 \times 7 \times 9}{ 5 \times 6 \times 7 \times 8} , \frac{3 \times 5 \times 7 \times 9 \times 11}{ 6 \times 7 \times 8 \times 9 \times 10}, \cdots \end{eqnarray*} Now multiply these by the second to last term \begin{eqnarray*} \frac{1}{1} ,\frac{3}{2} , \frac{ 5}{ 4} ,\frac{7}{8} \times \frac{3}{2} ,\frac{ 9}{ 8} \times \frac{ 5}{ 4}, \frac{ 11}{ 16} \times \frac{21}{16}, \cdots \end{eqnarray*}

0
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As far as I know there is no systematic approach to find the nth term of a sequence given a few terms, it's more like a creativity thing. Furthermore, I guess there are many (infinite?) sequences that would fit the first given N terms. For example for your numerators it may work $|n-3| (n+1)$