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| Mirrors > Home > MPE Home > Th. List > df-vrmd | Structured version Visualization version GIF version | ||
| Description: Define a free monoid over a set 𝑖 of generators, defined as the set of finite strings on 𝐼 with the operation of concatenation. (Contributed by Mario Carneiro, 27-Sep-2015.) | 
| Ref | Expression | 
|---|---|
| df-vrmd | ⊢ varFMnd = (𝑖 ∈ V ↦ (𝑗 ∈ 𝑖 ↦ 〈“𝑗”〉)) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | cvrmd 18861 | . 2 class varFMnd | |
| 2 | vi | . . 3 setvar 𝑖 | |
| 3 | cvv 3480 | . . 3 class V | |
| 4 | vj | . . . 4 setvar 𝑗 | |
| 5 | 2 | cv 1539 | . . . 4 class 𝑖 | 
| 6 | 4 | cv 1539 | . . . . 5 class 𝑗 | 
| 7 | 6 | cs1 14633 | . . . 4 class 〈“𝑗”〉 | 
| 8 | 4, 5, 7 | cmpt 5225 | . . 3 class (𝑗 ∈ 𝑖 ↦ 〈“𝑗”〉) | 
| 9 | 2, 3, 8 | cmpt 5225 | . 2 class (𝑖 ∈ V ↦ (𝑗 ∈ 𝑖 ↦ 〈“𝑗”〉)) | 
| 10 | 1, 9 | wceq 1540 | 1 wff varFMnd = (𝑖 ∈ V ↦ (𝑗 ∈ 𝑖 ↦ 〈“𝑗”〉)) | 
| Colors of variables: wff setvar class | 
| This definition is referenced by: vrmdfval 18869 | 
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