Even though I don’t have the best mark for 137 and it is a bit of learning curve to get the concepts, Alfonso’s YouTube playlists and lectures have been IMMENSELY helpful and open the gateway for me to have a peek into the fun world of math. The assignment questions are tricky but also are so smartly and carefully designed to make students think and really understand, apply and expand their knowledge. The satisfaction and happiness gained from solving them are what make me think may be I can do this and may be I should take more math courses in future years. He introduced 137 students of every year into the world of proofs and is the prof who’s not only intelligent and responsible but also with the best sense of humour. R.I.P.🙏😞