Theorems · Theorem · group theory
Subgroup.index_comap
∀ {G : Type u_1} {G' : Type u_2} [inst : Group G] [inst_1 : Group G'] (H : Subgroup G) (f : G' →* G),
(Subgroup.comap f H).index = H.relIndex f.range- Defined in
- Mathlib.GroupTheory.Index
- Cited by
- 5 results in Mathlib
- Foundations
- Depth 95 from the axioms · uses propext, Classical.choice, Quot.sound
Around this declaration
Dashed lines are statement dependencies; solid lines are citations in proofs.
Cites10
Mathlib declarations this one mentions in its statement or cites explicitly in its proof. Plumbing is filtered out.
- Groupstatement and proof · cited by 6,238
- MonoidHomstatement and proof · cited by 3,629
- Subgroupstatement and proof · cited by 3,593
- MonoidHom.rangestatement and proof · cited by 314
- Subgroup.comapstatement and proof · cited by 154
- Subgroup.indexstatement and proof · cited by 150
- Subgroup.subgroupOfproof · cited by 122
- Subgroup.relIndexstatement · cited by 72
- MonoidHom.rangeRestrict_surjectiveproof · cited by 6
- Subgroup.index_comap_of_surjectiveproof · cited by 5
Cited by5
Results whose statement or proof uses this declaration.
- Subgroup.index_kerproof · cited by 7
- Subgroup.relIndex_comapproof · cited by 7
- Subgroup.index_mapproof · cited by 6
- Subgroup.relIndex_subgroupOfproof · cited by 1
- CongruenceSubgroup.finiteIndex_conjGLproof · cited by 0