Metamath Proof Explorer


Theorem s7cli

Description: A length 7 string is a word. (Contributed by Mario Carneiro, 26-Feb-2016)

Ref Expression
Assertion s7cli ⟨“ 𝐴 𝐵 𝐶 𝐷 𝐸 𝐹 𝐺 ”⟩ ∈ Word V

Proof

Step Hyp Ref Expression
1 df-s7 ⟨“ 𝐴 𝐵 𝐶 𝐷 𝐸 𝐹 𝐺 ”⟩ = ( ⟨“ 𝐴 𝐵 𝐶 𝐷 𝐸 𝐹 ”⟩ ++ ⟨“ 𝐺 ”⟩ )
2 s6cli ⟨“ 𝐴 𝐵 𝐶 𝐷 𝐸 𝐹 ”⟩ ∈ Word V
3 1 2 cats1cli ⟨“ 𝐴 𝐵 𝐶 𝐷 𝐸 𝐹 𝐺 ”⟩ ∈ Word V