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citations	visibility	version 1	version 1	(static HELM directory)	helena

Informal description: ""

{λ[a:Prop] .​ λ[b:Prop] .​ λ[n:(a) .​ not ] .​ λ[m:(b) .​ not ]} .​ <({(b) .​ (a)} .​ or ) .​ not > .​ {(m) .​ (n) .​ (b) .​ ((a) .​ not )} .​ th4

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