Conversation so far:
What University did Gottlob Frege attend?
University of Jena.
What did he study at Jena?
he attended approximately twenty courses of lectures, most of them on mathematics and physics.
Did he then transfer to Gottingen?
Frege continued his studies in Gottingen.

Question: What did he study at Gottingen?
Self-contained rewrite: What did Gottlob Frege study at Gottingen?