The tool does not recognize `λn. n` as eta-equivalent to the Church 1 (`λfn. f n`).

This might prevent it from recognizing `E := λmn. n m` as a solution to the exponentiation problem. (I can't check it right now). But it certainly does not help when testing.

Start by reproducing the two lambda expressions in the project's REPL and inspect the equivalence-checking entry point. Verify the behavior for `λn. n` versus Church 1, then check whether `E := λmn. n m` is recognized as an exponentiation solution; done means the intended equivalence is recognized and covered by a repeatable test.

Written by the indexing model from the issue text.