Canonical Ohm_igFun i := [igFun by Ohm_sub i & Ohm_cont i].
Canonical Ohm_gFun i := [gFun by Ohm_cont i].
Canonical Ohm_mgFun i := [mgFun by OhmS i].
Canonical Mho_igFun i := [igFun by Mho_sub i & Mho_cont i].
Canonical Mho_gFun i := [gFun by Mho_cont i].
Canonical Mho_mgFun i := [mgFun by MhoS i].
Section char.
Variables (n : nat) (gT rT : finGroupType) (D G : {group gT}).

Lemma p_rank_abelian p G : abelian G -> 'r_p(G) = logn p #|'Ohm_1(G)|.