Skip to main content
6 events
when toggle format what by license comment
Aug 6, 2023 at 12:20 comment added Dave Benson Between $10^{50}$ and $10^{50}+10^6$ there are still six of them.
Aug 6, 2023 at 12:13 comment added Dave Benson This doesn't answer your question, but if $p$ is a prime such that $6p+1$ and $12p+1$ are also primes then $|PSL(2,12p+1)|=12p(6p+1)(12p+1)$ has only five distinct prime factors. It would follow from the Generalised Bunyakovsky Conjecture that there are infinitely many of these, and they do seem pretty dense. For example between $10^{15}$ and $10^{15}+10^6$ there are $137$ of them, the first few of which are 1000000000007651, 1000000000012933, 1000000000021171, 1000000000026271, ...
Feb 19, 2023 at 11:44 comment added W4cc0 @YCor I know, in fact "subgroup" is a way stronger requirement in this case than "subquotient", but that's why I feel it should be possible to prove the result in this case (to give a negative answer in fact)
Feb 19, 2023 at 11:36 comment added YCor "Being a subgroup" is maybe not always natural, as opposed to "being a subquotient". For instance, the standard embedding $\mathrm{SL}_n\to\mathrm{SL}_{n+1}$ does not induce an embedding from $\mathrm{PSL}_n$ into $\mathrm{PSL}_{n+1}$.
Feb 19, 2023 at 11:33 history edited YCor CC BY-SA 4.0
added quotation, added tag, formatting
Feb 19, 2023 at 11:15 history asked W4cc0 CC BY-SA 4.0