(ARITY-IFF
 (20 20 (:REWRITE DEFAULT-CDR))
 (20 4 (:DEFINITION LEN))
 (16 16 (:REWRITE DEFAULT-CAR))
 (8 4 (:REWRITE DEFAULT-+-2))
 (4 4 (:REWRITE DEFAULT-+-1))
 (2 2 (:REWRITE DEFAULT-COERCE-2))
 (2 2 (:REWRITE DEFAULT-COERCE-1))
 (1 1 (:REWRITE ARITIES-OKP-IMPLIES-ARITY))
 )
