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Define the outer-semi direct product in the standard way

https://en.wikipedia.org/wiki/Semidirect_product#Outer_semidirect_products

I found out that $Q_8$ is the smallest finite group that is neither finite simple, nor can be expressed as an outer-semi-direct product of other groups.

What is the next smallest finite group (/set of smallest finite groups if they share the same order) that cannot be expressed an outer-semi-direct product?

(i'm not looking for a proof, just the names of these group(s))

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    What about a cyclic group of order $4$? – 2017-02-19
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    ah i'm silly, and thanks! that works – 2017-02-19

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It's not true that $Q_8$ is the smallest such group: the smallest such group is a cyclic group of order $4$. The next smallest such group after $Q_8$ is a cyclic group of order $9$.