Metamath Proof Explorer


Theorem cznrnglem

Description: Lemma for cznrng : The base set of the ring constructed from a Z/nZ structure by replacing the (multiplicative) ring operation by a constant operation is the base set of the Z/nZ structure. (Contributed by AV, 16-Feb-2020)

Ref Expression
Hypotheses cznrng.y ⊢ Y = ℤ/Nℤ
cznrng.b ⊢ B = Base Y
cznrng.x ⊢ X = Y sSet ⋅ ndx x ∈ B , y ∈ B ⟼ C
Assertion cznrnglem ⊢ B = Base X

Proof

Step Hyp Ref Expression
1 cznrng.y ⊢ Y = ℤ/Nℤ
2 cznrng.b ⊢ B = Base Y
3 cznrng.x ⊢ X = Y sSet ⋅ ndx x ∈ B , y ∈ B ⟼ C
4 baseid ⊢ Base = Slot Base ndx
5 basendxnmulrndx ⊢ Base ndx ≠ ⋅ ndx
6 4 5 setsnid ⊢ Base Y = Base Y sSet ⋅ ndx x ∈ B , y ∈ B ⟼ C
7 3 eqcomi ⊢ Y sSet ⋅ ndx x ∈ B , y ∈ B ⟼ C = X
8 7 fveq2i ⊢ Base Y sSet ⋅ ndx x ∈ B , y ∈ B ⟼ C = Base X
9 2 6 8 3eqtri ⊢ B = Base X