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Given any positive integer $n$, is the number of distinct groups of order $n$ upto isomorphism finite?

Thanks in advance.

D. N.
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    How many binary operations can you think of in a set of $n$ elements? Forget group axioms for a while. – Jyrki Lahtonen Aug 13 '13 at 06:02
  • @Jyrki Lahtonen: It is finite. I dont know exactly how many? – D. N. Aug 13 '13 at 06:08
  • Related: http://math.stackexchange.com/questions/422120/known-bounds-for-the-number-of-groups-of-a-given-order, http://math.stackexchange.com/questions/258753/a-set-of-non-isomorphic-finite-groups-is-a-finite-set – Jonas Meyer Aug 13 '13 at 06:29
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    deibor, so you were able to answer the question yourself! Good! Oh, and the number is just $n^{n^2}$ as the operation is just a function from a set of size $n^2$ to a set of size $n$. – Jyrki Lahtonen Aug 13 '13 at 06:33

2 Answers2

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Yes, there are finitely many maps $G\times G\to G$.

Alex Youcis
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Yes. Any such group is a subgroup of $S_n$, the symmetric group on $n$ elements. There are only finitely many such subgroups.