Let x0 of type ι be given.
Apply H0 with
odd_nat (ordsucc x0).
Assume H1:
x0 ∈ omega.
Apply exactly1of2_E with
even_nat x0,
even_nat (ordsucc x0),
odd_nat (ordsucc x0) leaving 3 subgoals.
Apply even_nat_xor_S with
x0.
Apply omega_nat_p with
x0.
The subproof is completed by applying H1.
Apply even_nat_or_odd_nat with
ordsucc x0,
odd_nat (ordsucc x0) leaving 3 subgoals.
Apply nat_ordsucc with
x0.
Apply omega_nat_p with
x0.
The subproof is completed by applying H1.
Apply FalseE with
odd_nat (ordsucc x0).
Apply H4.
The subproof is completed by applying H5.
The subproof is completed by applying H5.