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Informal description: ""

{λ[sigma:Set] .​ λ[tau:Set] .​ λ[f:Π[x:sigma] .​ tau] .​ λ[s0:sigma] .​ λ[t0:sigma] .​ λ[s:{(f) .​ (tau) .​ (sigma)} .​ surjective ]} .​ <{({(t0) .​ (s0) .​ (f) .​ (tau) .​ (sigma)} .​ changef ) .​ (tau) .​ (sigma)} .​ surjective > .​ {(s) .​ ({(t0) .​ (s0) .​ (sigma)} .​ th2 ) .​ (f) .​ ({(t0) .​ (s0) .​ (sigma)} .​ wissel ) .​ (tau) .​ (sigma) .​ (sigma)} .​ th1

Validation parameters: sort hierarchy = "Z2", kernel options = ""