Has anyone ever attempted a list of theorems ranked by the number of published proofs? Maybe such a table could have a column listing the number of known proofs (although it may be optimistic to think that any count is complete).
A guess:
Pythagorean theorem
Law of quadratic reciprocity
Algebraic closure of the field of complex numbers (known as the fundamental theorem of algebra, but some object to that name as a misnomer that may confuse students)
???
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