fact: Definition ra_cst_n n x : recalg n := ra_comp (ra_cst x) vec_nil.
imports: Arith List Lia Undecidability.Shared.Libs.DLW(utils_tac utils_nat utils_list gcd crt sums finite pos vec) Undecidability.MuRec.Util(recalg recomp prim_min)