Denot : $N(n)$ : the number of groupfs of order $n$ ?
Is there a number $n$ with $N(n)=22$ ?
Checking the first about $2000$ numbers, I noticed that there is no $n\in [1,2000]$ with $N(n)=22$. Does such an $n$ exist ? And if no, why ?
Generalization : Given a number $k$, can we determine whether there is a $n$ with $N(n)=k$ in a reasonable time ?
According to Maple, there are a number of values of $n < 50000$ for which $N(n) = 22$:
There is a conjecture that $N$ is surjective, but to my knowledge, there is little progress on this problem.