Metamath Proof Explorer


Theorem fincygsubgd

Description: The subgroup referenced in fincygsubgodd is a subgroup. (Contributed by Rohan Ridenour, 3-Aug-2023)

Ref Expression
Hypotheses fincygsubgd.1 𝐵 = ( Base ‘ 𝐺 )
fincygsubgd.2 · = ( .g𝐺 )
fincygsubgd.3 𝐻 = ( 𝑛 ∈ ℤ ↦ ( 𝑛 · ( 𝐶 · 𝐴 ) ) )
fincygsubgd.4 ( 𝜑𝐺 ∈ Grp )
fincygsubgd.5 ( 𝜑𝐴𝐵 )
fincygsubgd.6 ( 𝜑𝐶 ∈ ℕ )
Assertion fincygsubgd ( 𝜑 → ran 𝐻 ∈ ( SubGrp ‘ 𝐺 ) )

Proof

Step Hyp Ref Expression
1 fincygsubgd.1 𝐵 = ( Base ‘ 𝐺 )
2 fincygsubgd.2 · = ( .g𝐺 )
3 fincygsubgd.3 𝐻 = ( 𝑛 ∈ ℤ ↦ ( 𝑛 · ( 𝐶 · 𝐴 ) ) )
4 fincygsubgd.4 ( 𝜑𝐺 ∈ Grp )
5 fincygsubgd.5 ( 𝜑𝐴𝐵 )
6 fincygsubgd.6 ( 𝜑𝐶 ∈ ℕ )
7 6 nnzd ( 𝜑𝐶 ∈ ℤ )
8 1 2 4 7 5 mulgcld ( 𝜑 → ( 𝐶 · 𝐴 ) ∈ 𝐵 )
9 1 2 3 4 8 cycsubgcld ( 𝜑 → ran 𝐻 ∈ ( SubGrp ‘ 𝐺 ) )