Apply FalseE to the current goal.
Apply Hord to the current goal.
Assume Hcore Haeb.
Apply Hcore to the current goal.
Assume Hcore2 HneqRR.
Apply Hcore2 to the current goal.
Assume Hcore3 HneqXX.
Apply Hcore3 to the current goal.
Assume Hcore4 HneqRat.
Apply Hcore4 to the current goal.
Assume HordX HneqR.
An exact proof term for the current goal is (HneqXX Hrefl).
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