Let x0 of type ι be given.
Apply unknownprop_e4d6e0bfb4ef6d52ee13edd54a77c8cc7f0a3af8ffb1b8da66d4f98842dd28b5 with
x0,
91630.. x0,
x0.
The subproof is completed by applying unknownprop_c6d721b795faf1c324094ad380dfe62a3a5dc2ef0b2edf42237be188f6768728 with x0.