Solving.Z3synSourcemk_univ ctx u construct a Z3 expression from a universe.
mk_axiom s s' construct the Z3 predicate associated to the Axiom Predicate
mk_cumul s s' construct the Z3 predicate associated to the Cumul Predicate
mk_rule s s' s'' construct the Z3 predicate associated to the Rule Predicate
register_vars vars i give bound for each variable var between 0 and i