The term {tt (logand $tau_1 ldots tau_n$)} denotes the bit-wise logical and of the objects denoted by $tau_1$ through $tau_n$.
(Undefined (Arity Logand))
(Instance-Of (Arity Logand) Undefined) (<- (Logandc1 ?X ?Y) (Logand (Lognot ?X) ?Y)) (<- (Logandc2 ?X ?Y) (Logand ?X (Lognot ?Y))) (<- (Lognand ?X ?Y) (Lognot (Logand ?X ?Y)))