| Step | Hyp | Ref
| Expression |
| 1 | | acsfiindd.1 |
. . . . . . 7
⊢ (𝜑 → 𝐴 ∈ (ACS‘𝑋)) |
| 2 | 1 | acsmred 16317 |
. . . . . 6
⊢ (𝜑 → 𝐴 ∈ (Moore‘𝑋)) |
| 3 | 2 | ad2antrr 762 |
. . . . 5
⊢ (((𝜑 ∧ 𝑆 ∈ 𝐼) ∧ 𝑠 ∈ (𝒫 𝑆 ∩ Fin)) → 𝐴 ∈ (Moore‘𝑋)) |
| 4 | | acsfiindd.2 |
. . . . 5
⊢ 𝑁 = (mrCls‘𝐴) |
| 5 | | acsfiindd.3 |
. . . . 5
⊢ 𝐼 = (mrInd‘𝐴) |
| 6 | | simplr 792 |
. . . . 5
⊢ (((𝜑 ∧ 𝑆 ∈ 𝐼) ∧ 𝑠 ∈ (𝒫 𝑆 ∩ Fin)) → 𝑆 ∈ 𝐼) |
| 7 | | inss1 3833 |
. . . . . . 7
⊢
(𝒫 𝑆 ∩
Fin) ⊆ 𝒫 𝑆 |
| 8 | | simpr 477 |
. . . . . . 7
⊢ (((𝜑 ∧ 𝑆 ∈ 𝐼) ∧ 𝑠 ∈ (𝒫 𝑆 ∩ Fin)) → 𝑠 ∈ (𝒫 𝑆 ∩ Fin)) |
| 9 | 7, 8 | sseldi 3601 |
. . . . . 6
⊢ (((𝜑 ∧ 𝑆 ∈ 𝐼) ∧ 𝑠 ∈ (𝒫 𝑆 ∩ Fin)) → 𝑠 ∈ 𝒫 𝑆) |
| 10 | 9 | elpwid 4170 |
. . . . 5
⊢ (((𝜑 ∧ 𝑆 ∈ 𝐼) ∧ 𝑠 ∈ (𝒫 𝑆 ∩ Fin)) → 𝑠 ⊆ 𝑆) |
| 11 | 3, 4, 5, 6, 10 | mrissmrid 16301 |
. . . 4
⊢ (((𝜑 ∧ 𝑆 ∈ 𝐼) ∧ 𝑠 ∈ (𝒫 𝑆 ∩ Fin)) → 𝑠 ∈ 𝐼) |
| 12 | 11 | ralrimiva 2966 |
. . 3
⊢ ((𝜑 ∧ 𝑆 ∈ 𝐼) → ∀𝑠 ∈ (𝒫 𝑆 ∩ Fin)𝑠 ∈ 𝐼) |
| 13 | | dfss3 3592 |
. . 3
⊢
((𝒫 𝑆 ∩
Fin) ⊆ 𝐼 ↔
∀𝑠 ∈ (𝒫
𝑆 ∩ Fin)𝑠 ∈ 𝐼) |
| 14 | 12, 13 | sylibr 224 |
. 2
⊢ ((𝜑 ∧ 𝑆 ∈ 𝐼) → (𝒫 𝑆 ∩ Fin) ⊆ 𝐼) |
| 15 | 2 | adantr 481 |
. . 3
⊢ ((𝜑 ∧ (𝒫 𝑆 ∩ Fin) ⊆ 𝐼) → 𝐴 ∈ (Moore‘𝑋)) |
| 16 | | acsfiindd.4 |
. . . 4
⊢ (𝜑 → 𝑆 ⊆ 𝑋) |
| 17 | 16 | adantr 481 |
. . 3
⊢ ((𝜑 ∧ (𝒫 𝑆 ∩ Fin) ⊆ 𝐼) → 𝑆 ⊆ 𝑋) |
| 18 | | simpr 477 |
. . . . . . . . . . . . . . 15
⊢ (((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) → 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) |
| 19 | | elfpw 8268 |
. . . . . . . . . . . . . . 15
⊢ (𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin) ↔ (𝑡 ⊆ (𝑆 ∖ {𝑥}) ∧ 𝑡 ∈ Fin)) |
| 20 | 18, 19 | sylib 208 |
. . . . . . . . . . . . . 14
⊢ (((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) → (𝑡 ⊆ (𝑆 ∖ {𝑥}) ∧ 𝑡 ∈ Fin)) |
| 21 | 20 | simpld 475 |
. . . . . . . . . . . . 13
⊢ (((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) → 𝑡 ⊆ (𝑆 ∖ {𝑥})) |
| 22 | 21 | difss2d 3740 |
. . . . . . . . . . . 12
⊢ (((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) → 𝑡 ⊆ 𝑆) |
| 23 | | simplr 792 |
. . . . . . . . . . . . 13
⊢ (((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) → 𝑥 ∈ 𝑆) |
| 24 | 23 | snssd 4340 |
. . . . . . . . . . . 12
⊢ (((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) → {𝑥} ⊆ 𝑆) |
| 25 | 22, 24 | unssd 3789 |
. . . . . . . . . . 11
⊢ (((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) → (𝑡 ∪ {𝑥}) ⊆ 𝑆) |
| 26 | 20 | simprd 479 |
. . . . . . . . . . . 12
⊢ (((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) → 𝑡 ∈ Fin) |
| 27 | | snfi 8038 |
. . . . . . . . . . . 12
⊢ {𝑥} ∈ Fin |
| 28 | | unfi 8227 |
. . . . . . . . . . . 12
⊢ ((𝑡 ∈ Fin ∧ {𝑥} ∈ Fin) → (𝑡 ∪ {𝑥}) ∈ Fin) |
| 29 | 26, 27, 28 | sylancl 694 |
. . . . . . . . . . 11
⊢ (((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) → (𝑡 ∪ {𝑥}) ∈ Fin) |
| 30 | | elfpw 8268 |
. . . . . . . . . . 11
⊢ ((𝑡 ∪ {𝑥}) ∈ (𝒫 𝑆 ∩ Fin) ↔ ((𝑡 ∪ {𝑥}) ⊆ 𝑆 ∧ (𝑡 ∪ {𝑥}) ∈ Fin)) |
| 31 | 25, 29, 30 | sylanbrc 698 |
. . . . . . . . . 10
⊢ (((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) → (𝑡 ∪ {𝑥}) ∈ (𝒫 𝑆 ∩ Fin)) |
| 32 | 2 | ad4antr 768 |
. . . . . . . . . . . . 13
⊢
(((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) ∧ 𝑠 ∈ 𝐼) → 𝐴 ∈ (Moore‘𝑋)) |
| 33 | | simpr 477 |
. . . . . . . . . . . . 13
⊢
(((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) ∧ 𝑠 ∈ 𝐼) → 𝑠 ∈ 𝐼) |
| 34 | | simpllr 799 |
. . . . . . . . . . . . . . . 16
⊢ ((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) → 𝑥 ∈ 𝑆) |
| 35 | | snidg 4206 |
. . . . . . . . . . . . . . . 16
⊢ (𝑥 ∈ 𝑆 → 𝑥 ∈ {𝑥}) |
| 36 | | elun2 3781 |
. . . . . . . . . . . . . . . 16
⊢ (𝑥 ∈ {𝑥} → 𝑥 ∈ (𝑡 ∪ {𝑥})) |
| 37 | 34, 35, 36 | 3syl 18 |
. . . . . . . . . . . . . . 15
⊢ ((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) → 𝑥 ∈ (𝑡 ∪ {𝑥})) |
| 38 | | simpr 477 |
. . . . . . . . . . . . . . 15
⊢ ((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) → 𝑠 = (𝑡 ∪ {𝑥})) |
| 39 | 37, 38 | eleqtrrd 2704 |
. . . . . . . . . . . . . 14
⊢ ((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) → 𝑥 ∈ 𝑠) |
| 40 | 39 | adantr 481 |
. . . . . . . . . . . . 13
⊢
(((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) ∧ 𝑠 ∈ 𝐼) → 𝑥 ∈ 𝑠) |
| 41 | 4, 5, 32, 33, 40 | ismri2dad 16297 |
. . . . . . . . . . . 12
⊢
(((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) ∧ 𝑠 ∈ 𝐼) → ¬ 𝑥 ∈ (𝑁‘(𝑠 ∖ {𝑥}))) |
| 42 | 2 | ad3antrrr 766 |
. . . . . . . . . . . . . . 15
⊢ ((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) → 𝐴 ∈ (Moore‘𝑋)) |
| 43 | 21 | adantr 481 |
. . . . . . . . . . . . . . . . . 18
⊢ ((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) → 𝑡 ⊆ (𝑆 ∖ {𝑥})) |
| 44 | | neldifsnd 4322 |
. . . . . . . . . . . . . . . . . 18
⊢ ((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) → ¬ 𝑥 ∈ (𝑆 ∖ {𝑥})) |
| 45 | 43, 44 | ssneldd 3606 |
. . . . . . . . . . . . . . . . 17
⊢ ((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) → ¬ 𝑥 ∈ 𝑡) |
| 46 | | difsnb 4337 |
. . . . . . . . . . . . . . . . 17
⊢ (¬
𝑥 ∈ 𝑡 ↔ (𝑡 ∖ {𝑥}) = 𝑡) |
| 47 | 45, 46 | sylib 208 |
. . . . . . . . . . . . . . . 16
⊢ ((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) → (𝑡 ∖ {𝑥}) = 𝑡) |
| 48 | | ssun1 3776 |
. . . . . . . . . . . . . . . . . 18
⊢ 𝑡 ⊆ (𝑡 ∪ {𝑥}) |
| 49 | 48, 38 | syl5sseqr 3654 |
. . . . . . . . . . . . . . . . 17
⊢ ((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) → 𝑡 ⊆ 𝑠) |
| 50 | 49 | ssdifd 3746 |
. . . . . . . . . . . . . . . 16
⊢ ((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) → (𝑡 ∖ {𝑥}) ⊆ (𝑠 ∖ {𝑥})) |
| 51 | 47, 50 | eqsstr3d 3640 |
. . . . . . . . . . . . . . 15
⊢ ((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) → 𝑡 ⊆ (𝑠 ∖ {𝑥})) |
| 52 | 25 | adantr 481 |
. . . . . . . . . . . . . . . . . 18
⊢ ((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) → (𝑡 ∪ {𝑥}) ⊆ 𝑆) |
| 53 | 16 | ad3antrrr 766 |
. . . . . . . . . . . . . . . . . 18
⊢ ((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) → 𝑆 ⊆ 𝑋) |
| 54 | 52, 53 | sstrd 3613 |
. . . . . . . . . . . . . . . . 17
⊢ ((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) → (𝑡 ∪ {𝑥}) ⊆ 𝑋) |
| 55 | 38, 54 | eqsstrd 3639 |
. . . . . . . . . . . . . . . 16
⊢ ((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) → 𝑠 ⊆ 𝑋) |
| 56 | 55 | ssdifssd 3748 |
. . . . . . . . . . . . . . 15
⊢ ((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) → (𝑠 ∖ {𝑥}) ⊆ 𝑋) |
| 57 | 42, 4, 51, 56 | mrcssd 16284 |
. . . . . . . . . . . . . 14
⊢ ((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) → (𝑁‘𝑡) ⊆ (𝑁‘(𝑠 ∖ {𝑥}))) |
| 58 | 57 | sseld 3602 |
. . . . . . . . . . . . 13
⊢ ((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) → (𝑥 ∈ (𝑁‘𝑡) → 𝑥 ∈ (𝑁‘(𝑠 ∖ {𝑥})))) |
| 59 | 58 | adantr 481 |
. . . . . . . . . . . 12
⊢
(((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) ∧ 𝑠 ∈ 𝐼) → (𝑥 ∈ (𝑁‘𝑡) → 𝑥 ∈ (𝑁‘(𝑠 ∖ {𝑥})))) |
| 60 | 41, 59 | mtod 189 |
. . . . . . . . . . 11
⊢
(((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) ∧ 𝑠 ∈ 𝐼) → ¬ 𝑥 ∈ (𝑁‘𝑡)) |
| 61 | 60 | ex 450 |
. . . . . . . . . 10
⊢ ((((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) ∧ 𝑠 = (𝑡 ∪ {𝑥})) → (𝑠 ∈ 𝐼 → ¬ 𝑥 ∈ (𝑁‘𝑡))) |
| 62 | 31, 61 | rspcimdv 3310 |
. . . . . . . . 9
⊢ (((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) → (∀𝑠 ∈ (𝒫 𝑆 ∩ Fin)𝑠 ∈ 𝐼 → ¬ 𝑥 ∈ (𝑁‘𝑡))) |
| 63 | 13, 62 | syl5bi 232 |
. . . . . . . 8
⊢ (((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ 𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)) → ((𝒫 𝑆 ∩ Fin) ⊆ 𝐼 → ¬ 𝑥 ∈ (𝑁‘𝑡))) |
| 64 | 63 | impancom 456 |
. . . . . . 7
⊢ (((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ (𝒫 𝑆 ∩ Fin) ⊆ 𝐼) → (𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin) → ¬ 𝑥 ∈ (𝑁‘𝑡))) |
| 65 | 64 | ralrimiv 2965 |
. . . . . 6
⊢ (((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ (𝒫 𝑆 ∩ Fin) ⊆ 𝐼) → ∀𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin) ¬ 𝑥 ∈ (𝑁‘𝑡)) |
| 66 | 16 | ssdifssd 3748 |
. . . . . . . . . 10
⊢ (𝜑 → (𝑆 ∖ {𝑥}) ⊆ 𝑋) |
| 67 | 1, 4, 66 | acsficl2d 17176 |
. . . . . . . . 9
⊢ (𝜑 → (𝑥 ∈ (𝑁‘(𝑆 ∖ {𝑥})) ↔ ∃𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)𝑥 ∈ (𝑁‘𝑡))) |
| 68 | 67 | notbid 308 |
. . . . . . . 8
⊢ (𝜑 → (¬ 𝑥 ∈ (𝑁‘(𝑆 ∖ {𝑥})) ↔ ¬ ∃𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)𝑥 ∈ (𝑁‘𝑡))) |
| 69 | | ralnex 2992 |
. . . . . . . 8
⊢
(∀𝑡 ∈
(𝒫 (𝑆 ∖
{𝑥}) ∩ Fin) ¬ 𝑥 ∈ (𝑁‘𝑡) ↔ ¬ ∃𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin)𝑥 ∈ (𝑁‘𝑡)) |
| 70 | 68, 69 | syl6bbr 278 |
. . . . . . 7
⊢ (𝜑 → (¬ 𝑥 ∈ (𝑁‘(𝑆 ∖ {𝑥})) ↔ ∀𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin) ¬ 𝑥 ∈ (𝑁‘𝑡))) |
| 71 | 70 | ad2antrr 762 |
. . . . . 6
⊢ (((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ (𝒫 𝑆 ∩ Fin) ⊆ 𝐼) → (¬ 𝑥 ∈ (𝑁‘(𝑆 ∖ {𝑥})) ↔ ∀𝑡 ∈ (𝒫 (𝑆 ∖ {𝑥}) ∩ Fin) ¬ 𝑥 ∈ (𝑁‘𝑡))) |
| 72 | 65, 71 | mpbird 247 |
. . . . 5
⊢ (((𝜑 ∧ 𝑥 ∈ 𝑆) ∧ (𝒫 𝑆 ∩ Fin) ⊆ 𝐼) → ¬ 𝑥 ∈ (𝑁‘(𝑆 ∖ {𝑥}))) |
| 73 | 72 | an32s 846 |
. . . 4
⊢ (((𝜑 ∧ (𝒫 𝑆 ∩ Fin) ⊆ 𝐼) ∧ 𝑥 ∈ 𝑆) → ¬ 𝑥 ∈ (𝑁‘(𝑆 ∖ {𝑥}))) |
| 74 | 73 | ralrimiva 2966 |
. . 3
⊢ ((𝜑 ∧ (𝒫 𝑆 ∩ Fin) ⊆ 𝐼) → ∀𝑥 ∈ 𝑆 ¬ 𝑥 ∈ (𝑁‘(𝑆 ∖ {𝑥}))) |
| 75 | 4, 5, 15, 17, 74 | ismri2dd 16294 |
. 2
⊢ ((𝜑 ∧ (𝒫 𝑆 ∩ Fin) ⊆ 𝐼) → 𝑆 ∈ 𝐼) |
| 76 | 14, 75 | impbida 877 |
1
⊢ (𝜑 → (𝑆 ∈ 𝐼 ↔ (𝒫 𝑆 ∩ Fin) ⊆ 𝐼)) |