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Description: Any word in a free monoid can be expressed as the sum of the singletons composing it. (Contributed by Mario Carneiro, 27-Sep-2015)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | frmdmnd.m | ⊢ 𝑀 = ( freeMnd ‘ 𝐼 ) | |
| frmdgsum.u | ⊢ 𝑈 = ( varFMnd ‘ 𝐼 ) | ||
| Assertion | frmdgsum | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ 𝑊 ∈ Word 𝐼 ) → ( 𝑀 Σg ( 𝑈 ∘ 𝑊 ) ) = 𝑊 ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | frmdmnd.m | ⊢ 𝑀 = ( freeMnd ‘ 𝐼 ) | |
| 2 | frmdgsum.u | ⊢ 𝑈 = ( varFMnd ‘ 𝐼 ) | |
| 3 | coeq2 | ⊢ ( 𝑥 = ∅ → ( 𝑈 ∘ 𝑥 ) = ( 𝑈 ∘ ∅ ) ) | |
| 4 | co02 | ⊢ ( 𝑈 ∘ ∅ ) = ∅ | |
| 5 | 3 4 | eqtrdi | ⊢ ( 𝑥 = ∅ → ( 𝑈 ∘ 𝑥 ) = ∅ ) |
| 6 | 5 | oveq2d | ⊢ ( 𝑥 = ∅ → ( 𝑀 Σg ( 𝑈 ∘ 𝑥 ) ) = ( 𝑀 Σg ∅ ) ) |
| 7 | id | ⊢ ( 𝑥 = ∅ → 𝑥 = ∅ ) | |
| 8 | 6 7 | eqeq12d | ⊢ ( 𝑥 = ∅ → ( ( 𝑀 Σg ( 𝑈 ∘ 𝑥 ) ) = 𝑥 ↔ ( 𝑀 Σg ∅ ) = ∅ ) ) |
| 9 | 8 | imbi2d | ⊢ ( 𝑥 = ∅ → ( ( 𝐼 ∈ 𝑉 → ( 𝑀 Σg ( 𝑈 ∘ 𝑥 ) ) = 𝑥 ) ↔ ( 𝐼 ∈ 𝑉 → ( 𝑀 Σg ∅ ) = ∅ ) ) ) |
| 10 | coeq2 | ⊢ ( 𝑥 = 𝑦 → ( 𝑈 ∘ 𝑥 ) = ( 𝑈 ∘ 𝑦 ) ) | |
| 11 | 10 | oveq2d | ⊢ ( 𝑥 = 𝑦 → ( 𝑀 Σg ( 𝑈 ∘ 𝑥 ) ) = ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) ) |
| 12 | id | ⊢ ( 𝑥 = 𝑦 → 𝑥 = 𝑦 ) | |
| 13 | 11 12 | eqeq12d | ⊢ ( 𝑥 = 𝑦 → ( ( 𝑀 Σg ( 𝑈 ∘ 𝑥 ) ) = 𝑥 ↔ ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) = 𝑦 ) ) |
| 14 | 13 | imbi2d | ⊢ ( 𝑥 = 𝑦 → ( ( 𝐼 ∈ 𝑉 → ( 𝑀 Σg ( 𝑈 ∘ 𝑥 ) ) = 𝑥 ) ↔ ( 𝐼 ∈ 𝑉 → ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) = 𝑦 ) ) ) |
| 15 | coeq2 | ⊢ ( 𝑥 = ( 𝑦 ++ 〈“ 𝑧 ”〉 ) → ( 𝑈 ∘ 𝑥 ) = ( 𝑈 ∘ ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) ) | |
| 16 | 15 | oveq2d | ⊢ ( 𝑥 = ( 𝑦 ++ 〈“ 𝑧 ”〉 ) → ( 𝑀 Σg ( 𝑈 ∘ 𝑥 ) ) = ( 𝑀 Σg ( 𝑈 ∘ ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) ) ) |
| 17 | id | ⊢ ( 𝑥 = ( 𝑦 ++ 〈“ 𝑧 ”〉 ) → 𝑥 = ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) | |
| 18 | 16 17 | eqeq12d | ⊢ ( 𝑥 = ( 𝑦 ++ 〈“ 𝑧 ”〉 ) → ( ( 𝑀 Σg ( 𝑈 ∘ 𝑥 ) ) = 𝑥 ↔ ( 𝑀 Σg ( 𝑈 ∘ ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) ) = ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) ) |
| 19 | 18 | imbi2d | ⊢ ( 𝑥 = ( 𝑦 ++ 〈“ 𝑧 ”〉 ) → ( ( 𝐼 ∈ 𝑉 → ( 𝑀 Σg ( 𝑈 ∘ 𝑥 ) ) = 𝑥 ) ↔ ( 𝐼 ∈ 𝑉 → ( 𝑀 Σg ( 𝑈 ∘ ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) ) = ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) ) ) |
| 20 | coeq2 | ⊢ ( 𝑥 = 𝑊 → ( 𝑈 ∘ 𝑥 ) = ( 𝑈 ∘ 𝑊 ) ) | |
| 21 | 20 | oveq2d | ⊢ ( 𝑥 = 𝑊 → ( 𝑀 Σg ( 𝑈 ∘ 𝑥 ) ) = ( 𝑀 Σg ( 𝑈 ∘ 𝑊 ) ) ) |
| 22 | id | ⊢ ( 𝑥 = 𝑊 → 𝑥 = 𝑊 ) | |
| 23 | 21 22 | eqeq12d | ⊢ ( 𝑥 = 𝑊 → ( ( 𝑀 Σg ( 𝑈 ∘ 𝑥 ) ) = 𝑥 ↔ ( 𝑀 Σg ( 𝑈 ∘ 𝑊 ) ) = 𝑊 ) ) |
| 24 | 23 | imbi2d | ⊢ ( 𝑥 = 𝑊 → ( ( 𝐼 ∈ 𝑉 → ( 𝑀 Σg ( 𝑈 ∘ 𝑥 ) ) = 𝑥 ) ↔ ( 𝐼 ∈ 𝑉 → ( 𝑀 Σg ( 𝑈 ∘ 𝑊 ) ) = 𝑊 ) ) ) |
| 25 | 1 | frmd0 | ⊢ ∅ = ( 0g ‘ 𝑀 ) |
| 26 | 25 | gsum0 | ⊢ ( 𝑀 Σg ∅ ) = ∅ |
| 27 | 26 | a1i | ⊢ ( 𝐼 ∈ 𝑉 → ( 𝑀 Σg ∅ ) = ∅ ) |
| 28 | oveq1 | ⊢ ( ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) = 𝑦 → ( ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) ++ 〈“ 𝑧 ”〉 ) = ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) | |
| 29 | simprl | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → 𝑦 ∈ Word 𝐼 ) | |
| 30 | simprr | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → 𝑧 ∈ 𝐼 ) | |
| 31 | 30 | s1cld | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → 〈“ 𝑧 ”〉 ∈ Word 𝐼 ) |
| 32 | 2 | vrmdf | ⊢ ( 𝐼 ∈ 𝑉 → 𝑈 : 𝐼 ⟶ Word 𝐼 ) |
| 33 | 32 | adantr | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → 𝑈 : 𝐼 ⟶ Word 𝐼 ) |
| 34 | ccatco | ⊢ ( ( 𝑦 ∈ Word 𝐼 ∧ 〈“ 𝑧 ”〉 ∈ Word 𝐼 ∧ 𝑈 : 𝐼 ⟶ Word 𝐼 ) → ( 𝑈 ∘ ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) = ( ( 𝑈 ∘ 𝑦 ) ++ ( 𝑈 ∘ 〈“ 𝑧 ”〉 ) ) ) | |
| 35 | 29 31 33 34 | syl3anc | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → ( 𝑈 ∘ ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) = ( ( 𝑈 ∘ 𝑦 ) ++ ( 𝑈 ∘ 〈“ 𝑧 ”〉 ) ) ) |
| 36 | s1co | ⊢ ( ( 𝑧 ∈ 𝐼 ∧ 𝑈 : 𝐼 ⟶ Word 𝐼 ) → ( 𝑈 ∘ 〈“ 𝑧 ”〉 ) = 〈“ ( 𝑈 ‘ 𝑧 ) ”〉 ) | |
| 37 | 30 33 36 | syl2anc | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → ( 𝑈 ∘ 〈“ 𝑧 ”〉 ) = 〈“ ( 𝑈 ‘ 𝑧 ) ”〉 ) |
| 38 | 2 | vrmdval | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ 𝑧 ∈ 𝐼 ) → ( 𝑈 ‘ 𝑧 ) = 〈“ 𝑧 ”〉 ) |
| 39 | 38 | adantrl | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → ( 𝑈 ‘ 𝑧 ) = 〈“ 𝑧 ”〉 ) |
| 40 | 39 | s1eqd | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → 〈“ ( 𝑈 ‘ 𝑧 ) ”〉 = 〈“ 〈“ 𝑧 ”〉 ”〉 ) |
| 41 | 37 40 | eqtrd | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → ( 𝑈 ∘ 〈“ 𝑧 ”〉 ) = 〈“ 〈“ 𝑧 ”〉 ”〉 ) |
| 42 | 41 | oveq2d | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → ( ( 𝑈 ∘ 𝑦 ) ++ ( 𝑈 ∘ 〈“ 𝑧 ”〉 ) ) = ( ( 𝑈 ∘ 𝑦 ) ++ 〈“ 〈“ 𝑧 ”〉 ”〉 ) ) |
| 43 | 35 42 | eqtrd | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → ( 𝑈 ∘ ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) = ( ( 𝑈 ∘ 𝑦 ) ++ 〈“ 〈“ 𝑧 ”〉 ”〉 ) ) |
| 44 | 43 | oveq2d | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → ( 𝑀 Σg ( 𝑈 ∘ ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) ) = ( 𝑀 Σg ( ( 𝑈 ∘ 𝑦 ) ++ 〈“ 〈“ 𝑧 ”〉 ”〉 ) ) ) |
| 45 | 1 | frmdmnd | ⊢ ( 𝐼 ∈ 𝑉 → 𝑀 ∈ Mnd ) |
| 46 | 45 | adantr | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → 𝑀 ∈ Mnd ) |
| 47 | wrdco | ⊢ ( ( 𝑦 ∈ Word 𝐼 ∧ 𝑈 : 𝐼 ⟶ Word 𝐼 ) → ( 𝑈 ∘ 𝑦 ) ∈ Word Word 𝐼 ) | |
| 48 | 29 33 47 | syl2anc | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → ( 𝑈 ∘ 𝑦 ) ∈ Word Word 𝐼 ) |
| 49 | eqid | ⊢ ( Base ‘ 𝑀 ) = ( Base ‘ 𝑀 ) | |
| 50 | 1 49 | frmdbas | ⊢ ( 𝐼 ∈ 𝑉 → ( Base ‘ 𝑀 ) = Word 𝐼 ) |
| 51 | 50 | adantr | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → ( Base ‘ 𝑀 ) = Word 𝐼 ) |
| 52 | wrdeq | ⊢ ( ( Base ‘ 𝑀 ) = Word 𝐼 → Word ( Base ‘ 𝑀 ) = Word Word 𝐼 ) | |
| 53 | 51 52 | syl | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → Word ( Base ‘ 𝑀 ) = Word Word 𝐼 ) |
| 54 | 48 53 | eleqtrrd | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → ( 𝑈 ∘ 𝑦 ) ∈ Word ( Base ‘ 𝑀 ) ) |
| 55 | 31 51 | eleqtrrd | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → 〈“ 𝑧 ”〉 ∈ ( Base ‘ 𝑀 ) ) |
| 56 | 55 | s1cld | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → 〈“ 〈“ 𝑧 ”〉 ”〉 ∈ Word ( Base ‘ 𝑀 ) ) |
| 57 | eqid | ⊢ ( +g ‘ 𝑀 ) = ( +g ‘ 𝑀 ) | |
| 58 | 49 57 | gsumccat | ⊢ ( ( 𝑀 ∈ Mnd ∧ ( 𝑈 ∘ 𝑦 ) ∈ Word ( Base ‘ 𝑀 ) ∧ 〈“ 〈“ 𝑧 ”〉 ”〉 ∈ Word ( Base ‘ 𝑀 ) ) → ( 𝑀 Σg ( ( 𝑈 ∘ 𝑦 ) ++ 〈“ 〈“ 𝑧 ”〉 ”〉 ) ) = ( ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) ( +g ‘ 𝑀 ) ( 𝑀 Σg 〈“ 〈“ 𝑧 ”〉 ”〉 ) ) ) |
| 59 | 46 54 56 58 | syl3anc | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → ( 𝑀 Σg ( ( 𝑈 ∘ 𝑦 ) ++ 〈“ 〈“ 𝑧 ”〉 ”〉 ) ) = ( ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) ( +g ‘ 𝑀 ) ( 𝑀 Σg 〈“ 〈“ 𝑧 ”〉 ”〉 ) ) ) |
| 60 | 49 | gsumws1 | ⊢ ( 〈“ 𝑧 ”〉 ∈ ( Base ‘ 𝑀 ) → ( 𝑀 Σg 〈“ 〈“ 𝑧 ”〉 ”〉 ) = 〈“ 𝑧 ”〉 ) |
| 61 | 55 60 | syl | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → ( 𝑀 Σg 〈“ 〈“ 𝑧 ”〉 ”〉 ) = 〈“ 𝑧 ”〉 ) |
| 62 | 61 | oveq2d | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → ( ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) ( +g ‘ 𝑀 ) ( 𝑀 Σg 〈“ 〈“ 𝑧 ”〉 ”〉 ) ) = ( ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) ( +g ‘ 𝑀 ) 〈“ 𝑧 ”〉 ) ) |
| 63 | 49 | gsumwcl | ⊢ ( ( 𝑀 ∈ Mnd ∧ ( 𝑈 ∘ 𝑦 ) ∈ Word ( Base ‘ 𝑀 ) ) → ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) ∈ ( Base ‘ 𝑀 ) ) |
| 64 | 46 54 63 | syl2anc | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) ∈ ( Base ‘ 𝑀 ) ) |
| 65 | 1 49 57 | frmdadd | ⊢ ( ( ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) ∈ ( Base ‘ 𝑀 ) ∧ 〈“ 𝑧 ”〉 ∈ ( Base ‘ 𝑀 ) ) → ( ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) ( +g ‘ 𝑀 ) 〈“ 𝑧 ”〉 ) = ( ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) ++ 〈“ 𝑧 ”〉 ) ) |
| 66 | 64 55 65 | syl2anc | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → ( ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) ( +g ‘ 𝑀 ) 〈“ 𝑧 ”〉 ) = ( ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) ++ 〈“ 𝑧 ”〉 ) ) |
| 67 | 62 66 | eqtrd | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → ( ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) ( +g ‘ 𝑀 ) ( 𝑀 Σg 〈“ 〈“ 𝑧 ”〉 ”〉 ) ) = ( ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) ++ 〈“ 𝑧 ”〉 ) ) |
| 68 | 59 67 | eqtrd | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → ( 𝑀 Σg ( ( 𝑈 ∘ 𝑦 ) ++ 〈“ 〈“ 𝑧 ”〉 ”〉 ) ) = ( ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) ++ 〈“ 𝑧 ”〉 ) ) |
| 69 | 44 68 | eqtrd | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → ( 𝑀 Σg ( 𝑈 ∘ ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) ) = ( ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) ++ 〈“ 𝑧 ”〉 ) ) |
| 70 | 69 | eqeq1d | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → ( ( 𝑀 Σg ( 𝑈 ∘ ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) ) = ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ↔ ( ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) ++ 〈“ 𝑧 ”〉 ) = ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) ) |
| 71 | 28 70 | imbitrrid | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) ) → ( ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) = 𝑦 → ( 𝑀 Σg ( 𝑈 ∘ ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) ) = ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) ) |
| 72 | 71 | expcom | ⊢ ( ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) → ( 𝐼 ∈ 𝑉 → ( ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) = 𝑦 → ( 𝑀 Σg ( 𝑈 ∘ ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) ) = ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) ) ) |
| 73 | 72 | a2d | ⊢ ( ( 𝑦 ∈ Word 𝐼 ∧ 𝑧 ∈ 𝐼 ) → ( ( 𝐼 ∈ 𝑉 → ( 𝑀 Σg ( 𝑈 ∘ 𝑦 ) ) = 𝑦 ) → ( 𝐼 ∈ 𝑉 → ( 𝑀 Σg ( 𝑈 ∘ ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) ) = ( 𝑦 ++ 〈“ 𝑧 ”〉 ) ) ) ) |
| 74 | 9 14 19 24 27 73 | wrdind | ⊢ ( 𝑊 ∈ Word 𝐼 → ( 𝐼 ∈ 𝑉 → ( 𝑀 Σg ( 𝑈 ∘ 𝑊 ) ) = 𝑊 ) ) |
| 75 | 74 | impcom | ⊢ ( ( 𝐼 ∈ 𝑉 ∧ 𝑊 ∈ Word 𝐼 ) → ( 𝑀 Σg ( 𝑈 ∘ 𝑊 ) ) = 𝑊 ) |