Module

SigmaMonotonicity.lean

Nyll.ProCGroups.FiniteGroups.SigmaMonotonicity
2 declarations indexed from sourceView source ↗

Inclusion of finite Sigma-group classes

Enlarging the permitted primes preserves the actual prime-divisor condition. No nonemptiness or primality assumption on the containing sets is needed.

Declarations

ProCGroups.FiniteGroupClass.IsSigmaNumber.mono

A Sigma-number remains admissible when the set of permitted primes grows.

Source context 2 commands

Surrounding namespaces, section variables, and local commands at this declaration.

namespace ProCGroups.FiniteGroupClass
universe u
theorem IsSigmaNumber.mono {sigma tau : Set ℕ} {n : ℕ}
    (h : sigma ⊆ tau) (hn : IsSigmaNumber sigma n) :
    IsSigmaNumber tau n
ProCGroups.FiniteGroupClass.sigmaGroup_mono

Inclusion of sets of primes gives inclusion of the corresponding finite-group classes.

Source context 2 commands

Surrounding namespaces, section variables, and local commands at this declaration.

namespace ProCGroups.FiniteGroupClass
universe u
theorem sigmaGroup_mono {sigma tau : Set ℕ} (h : sigma ⊆ tau)
    {G : Type u} [Group G] (hG : sigmaGroup sigma G) : sigmaGroup tau G