[repsilat]

> an algo for finding the longest palindromic subsequence (!)

Not irrelevant to my professional career, to be honest. There have been a few situations where being able to see a tricky, unfamiliar problem and after some thought say, "oh, we can use a DP algo for that" has saved a large amount of future headache.

Only a small fraction of people on the team need to have that skill (more in some teams than others, too) so I don't think it's a great thing to test for (much less require), but it's actually a pretty valuable skill in my experience.