Writing a proof in TLA

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marta zhango

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Apr 25, 2024, 4:07:40 PM4/25/24
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How can I write the proof for the number of permutations of n distinct objects
using TLA ?  In the form of a structured proof for teaching mathematics rather
than the code intended for the complete description for running in a proof system
like Coq or Lean.

I want to have something like page 24 and 25 in

Or something like Thearem 22 on page 31 in

This is my usual proof

 Let S = {a1,a2,...an}

First Choice c1 \in S
Cardinality(c1) = n

Second Choice (Remove previous c1)
c2 \in S\{c1} (remove first choice c1)
Cardinality(c2) = n-1

Continued Choice ci \in S\{c1,c2,...,c{i-1}}
Cardinality(ci) = n-(i-1)

Final Choice cn \in S\{c1,c2,...,c{n-1}}
Cardinality(cn) = 1

Thus Cardinality(S) = n!
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