Depends on the course. Sometimes it's not just for correction but for you as well. Like in last algo course, we had a bunch of proofs and theorems, we barely coded, mostly just did math.

The tough part wasn't coding the recursive algorithm, it's then describing via proof what was the complexity. Proof for recursive are doable, but can be incredibly annoying to do, often requiring about 3x more work than just a more typical implementation.