Recursive definition of logxor.
Theorem:
(defthm logxor* (implies (and (force (integerp i)) (force (integerp j))) (equal (logxor i j) (logcons (b-xor (logcar i) (logcar j)) (logxor (logcdr i) (logcdr j))))) :rule-classes ((:definition :clique (binary-logxor) :controller-alist ((binary-logxor t t)))))