If $tau_1$, ..., $tau_n$ are numerical constants, then the term {tt (+ $tau_1 ... tau_n$)} denotes the sum $tau$ of the numbers
corresponding to those constants.
(Undefined (Arity +))
(Instance-Of (Arity +) Undefined) (<- (1+ ?X) (+ ?X 1)) (<- (Fround ?X) (Ffloor (+ 0.5 ?X)))