fact: Definition nds_induction a b (T: fterm2) := transfinite_defined Nat_order (fun u => Yo (source u = \0c) a (Yo (source u = \1c) b (T (nds_k_of (source u)) (Vf u ((source u) -c (nds_k_of (source u))))))).
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat)