Theorems · Theorem · group theory
IsAddTorsion.extension_closed
∀ {G : Type u_1} {H : Type u_2} [inst : AddGroup G] {N : AddSubgroup G} [inst_1 : AddGroup H] {f : G →+ H},
N = f.ker → IsAddTorsion H → IsAddTorsion ↥N → IsAddTorsion GTorsion additive groups are closed under extensions.
- Defined in
- Mathlib.GroupTheory.Torsion
- Cited by
- 2 results in Mathlib
- Foundations
- Depth 27 from the axioms · uses propext, Quot.sound
Around this declaration
Dashed lines are statement dependencies; solid lines are citations in proofs.
Cites14
Mathlib declarations this one mentions in its statement or cites explicitly in its proof. Plumbing is filtered out.
- DFunLike.coeproof · cited by 62,936
- AddGroupstatement and proof · cited by 4,410
- AddSubgroupstatement and proof · cited by 3,232
- AddMonoidHomstatement and proof · cited by 3,230
- mul_posproof · cited by 374
- AddMonoidHom.kerstatement and proof · cited by 158
- IsAddTorsionstatement and proof · cited by 42
- isOfFinAddOrder_iff_nsmul_eq_zeroproof · cited by 27
- AddMonoidHom.mem_kerproof · cited by 26
- mul_nsmulproof · cited by 24
- AddMonoidHom.map_nsmulproof · cited by 18
- IsOfFinAddOrder.exists_nsmul_eq_zeroproof · cited by 6
Cited by2
Results whose statement or proof uses this declaration.
- IsAddTorsion.quotient_iffproof · cited by 1
- AddIsTorsion.extension_closedproof · cited by 0