Nevermind 7000 messages... 17 would be intractable.

Perhaps I neglected to mention that I once wrote a recursive brute-force program and, being careless because I knew n would never be more than 20 or so, inadvertently wrote it in such a way that it not only ran in O((n^2)!) time, but also used (n^2)! RAM. Err, well, (n^2)! swapfile space, actually. It worked okay for n=3, but when I tried to run it for n=4... let's just say I don't recommend this technique.

$;=sub{$/};@;=map{my($a,$b)=($_,$;);$;=sub{$a.$b->()}}
split//,".rekcah lreP rehtona tsuJ";$\=$ ;->();print$/
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