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Informal description: ""

{λ[a:Prop] .​ λ[b:Prop] .​ λ[c:Prop] .​ λ[i:{(b) .​ (a)} .​ iff ] .​ λ[e:{(a) .​ (c)} .​ ec ]} .​ <{(b) .​ (c)} .​ ec > .​ {({(i) .​ (b) .​ (a)} .​ iffe2 ) .​ (e) .​ (b) .​ (a) .​ (c)} .​ th4

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