Calculate a formula in tableaux method

let frm = Formula.Impl(Conj(Var "P", Var "Q"), Bic(Var "R", Neg(Var "S")))
let formulaCalcList = BuildFormulaCalcList frm |> List.sortBy(fun f -> CalcFormulaDepth f)
formulaCalcList |> List.map VerboseFormula |> List.iter(fun f -> printf "%s\t" f)
let formulaInterpritations = BuildAllFormulasInterpritations formulaCalcList
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