OAI/GroupTheory/PolycyclicRecognition/Algebra/Polycyclic.lean
9 declarations, 0 contain sorry, 0 declared as axioms
Polycyclic and virtually polycyclic groups
We use the existing concrete cyclic subnormal series, including normality and cyclicity of each quotient. Neither polycyclicity nor virtual polycyclicity is an unspecified property parameter.
- def
OAI.PolycyclicRecognition.IsPolycyclicline 22Source documentation
A polycyclic group has a finite subnormal series from the trivial subgroup to the whole group with cyclic factors.
Also declared: ComparatorChallenges/PolycyclicRecognition.lean:61 (same declaration text).
def IsPolycyclic : Prop := …
- def
OAI.PolycyclicRecognition.IsVirtuallyPolycyclicline 26Source documentation
A virtually polycyclic group contains a polycyclic subgroup of finite index.
Distinct definitions of this name: ComparatorChallenges/PolycyclicRecognition.lean:65 (same statement text; different proof or body). Qualify references as OAI.PolycyclicRecognition.IsVirtuallyPolycyclic@path.
def IsVirtuallyPolycyclic : Prop := …
- theorem
OAI.PolycyclicRecognition.isPolycyclic_of_subsingletonline 32Source documentation
The length-zero series proves polycyclicity of the trivial group.
theorem isPolycyclic_of_subsingleton [Subsingleton G] : IsPolycyclic G := by …
Mentions: OAI.PolycyclicRecognition.IsPolycyclic
- theorem
OAI.PolycyclicRecognition.IsPolycyclic.of_surjectiveline 39Source documentation
Polycyclicity descends to a surjective image by mapping a cyclic series.
theorem IsPolycyclic.of_surjective (hG : IsPolycyclic G) (f : G →* H) (hf : Function.Surjective f) : IsPolycyclic H := by …Mentions: OAI.PolycyclicRecognition.IsPolycyclic
- theorem
OAI.PolycyclicRecognition.IsPolycyclic.of_injectiveline 48Source documentation
Subgroups of polycyclic groups are polycyclic, by pulling back the cyclic series.
theorem IsPolycyclic.of_injective (hG : IsPolycyclic G) (f : H →* G) (hf : Function.Injective f) : IsPolycyclic H := by …Mentions: OAI.PolycyclicRecognition.IsPolycyclic
- theorem
OAI.PolycyclicRecognition.isPolycyclic_equivline 58Source documentation
This formulation is invariant under group isomorphisms.
theorem isPolycyclic_equiv (e : G ≃* H) : IsPolycyclic G ↔ IsPolycyclic H := …
Mentions: OAI.PolycyclicRecognition.IsPolycyclic
- theorem
OAI.PolycyclicRecognition.IsPolycyclic.isVirtuallyPolycyclicline 63Source documentation
A polycyclic group is virtually polycyclic, using the whole group.
theorem IsPolycyclic.isVirtuallyPolycyclic (hG : IsPolycyclic G) : IsVirtuallyPolycyclic G := by …Mentions: OAI.PolycyclicRecognition.IsPolycyclic
- theorem
OAI.PolycyclicRecognition.isVirtuallyPolycyclic_of_finiteline 70Source documentation
Every finite group is virtually polycyclic, via its trivial subgroup. The ambient finite group itself need not be solvable.
theorem isVirtuallyPolycyclic_of_finite [Finite G] : IsVirtuallyPolycyclic G := …
- theorem
OAI.PolycyclicRecognition.IsVirtuallyPolycyclic.of_injectiveline 74Source documentation
A subgroup of a virtually polycyclic group is virtually polycyclic.
theorem IsVirtuallyPolycyclic.of_injective (hG : IsVirtuallyPolycyclic G) (f : H →* G) (hf : Function.Injective f) : IsVirtuallyPolycyclic H := by …