Conclusions
    
      - A way to start formalizing with Lean:
        
          - "Natural Number Game"
            
              - helpful to master the thinking on the low
					 level
 
            
           
          - "Mathematics in Lean"
            
              - working through at least the first three
					 chapters and exercises
 
              -  → enough proficiency to cope with examples 1
					 and 2
 
            
           
          - 
				  "Formalising Mathematics"
            
              - online course with a strong focus on
					 Mathlib
 
              - explains the most important tactics and how to
					 apply them
 
              - comes with a useful list of Lean tips
 
            
           
          - skimming through the Mathlib files on matrices and
				linear algebra
 
          - asking concrete questions on the Lean Zulip chat
				server
 
        
       
      - Practicable for teaching?
        
          - teaching to formalize proofs
            
              - learning effort too high for first-year
					 students
 
            
           
          - presenting formalized proofs
            
              - could be helpful to understand structure and
					 logic of a proof
 
              - example 1: how to find subgoals or organize
					 steps in a calculation
 
              - example 2: how to cope with quantifiers in a
					 proof
 
            
           
          - example 3: too difficult
            
              - highly abstract formulation of Mathlib
 
              - basic material from linear algebra still
					 missing
 
            
           
        
       
      - What to do:
        
          - learn it yourself - it's fun (for a
				mathematician)
 
          - use it to present clearer, better structured
				proofs
 
          - maybe present a few formalized proofs in the
				lecture
 
          - keep an open eye on the rapid development