That's the problem. Someone made a nice set of "programming koans" that were (koans + exercises). But, that has spawned new "programming koans" that are just a set of (exercises) with no koans. Koans are supposed to involve practice [0]. But, does practicing a set of (koans + exercises - koans) have koan-nature? ;)
[0] https://en.wikipedia.org/wiki/K%C5%8Dan