How to find an example of a non Abelian group of arbitrary finite order? eg. $39$

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I was thinking of building on top of known non Abelian groups, like $S_3$, and taking a direct product with $\Bbb Z_n$'s but those groups' order would be a multiple of order of $S_3$.

  • So, is there is a clever way to do it for any order, like use an Abelian group of order close to, say $39$, and make it non-Abelian?
  • Here, Finding presentation of group of order 39 they give a general representation but can we come up with an actual example without using Sylow theorems? Appreciate your response.
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There are composite orders (e.g. 15 or 765, or prime squares) such that all groups of that order will be abelian, and there is no all-purpose construction, but here are a few constructions of nonabelian groups that cover lots of orders:

  • If the order is even and $>4$, one can construct a dihedral group.

  • If the order involves a prime power $p^k$ such that another prime divisor (that could be $p$ as well, so this in particular covers all orders that are multiples of a prime cubed) that divides the order of $GL_k(p)$, one can form a nonabelian semidirect product.