Alpha Equivalence in Lambda Calculus from the Haskell book by Allen And Moronuki
From page 45 of Haskell Programming from first Principles by Christopher Allen and Julie Moronuki:
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Exercise
3. 𝜆𝑥𝑦𝑧.𝑧𝑥
a) 𝜆𝑥.(𝜆𝑦.(𝜆𝑧.𝑧))
b) 𝜆𝑡𝑜𝑠.𝑠𝑡
c) 𝜆𝑚𝑛𝑝.𝑚𝑛
Which is correct?
I believe the answer is b).
Not a) because a) omits x.
Not c) because c) should be 𝜆𝑚𝑛𝑝.𝑝𝑚 NOT𝜆𝑚𝑛𝑝.𝑚𝑛