Lean4

Cover every constructor

cases l <;> rfl proves a cycle for all three lights.

10 minIntermediate
0/5 completed in this course
Lean workspaceWrite only the proof steps. The theorem above is fixed.
Enter after constructor adds both goal bullets
Exercise.leanLean 4.30.0
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ReadyLn 1, Col 1Pre-check passedLean 4