fact: Definition type_of_tuple (A : finType) n (ta : n.+1.-tuple A) : P_ n.+1 ( A ).
imports: mathcomp(all_ssreflect ssralg ssrnum perm) mathcomp(matrix) mathcomp(Rstruct) Reals ssrR Reals_ext realType_ext ssr_ext ssralg_ext logb fdist proba entropy num_occ channel_code channel typ_seq