Metamath Proof Explorer


Theorem conway

Description: Conway's Simplicity Theorem. Given A preceeding B , there is a unique surreal of minimal length separating them. This is a fundamental property of surreals and will be used (via surreal cuts) to prove many properties later on. Theorem from Alling p. 185. (Contributed by Scott Fenton, 8-Dec-2021)

Ref Expression
Assertion conway ⊢ A ≪ s B → ∃! x ∈ y ∈ No | A ≪ s y ∧ y ≪ s B bday ⁡ x = ⋂ bday y ∈ No | A ≪ s y ∧ y ≪ s B

Proof

Step Hyp Ref Expression
1 sltsss1 ⊢ A ≪ s B → A ⊆ No
2 sltsex1 ⊢ A ≪ s B → A ∈ V
3 sltsss2 ⊢ A ≪ s B → B ⊆ No
4 sltsex2 ⊢ A ≪ s B → B ∈ V
5 sltssep ⊢ A ≪ s B → ∀ p ∈ A ∀ q ∈ B p < s q
6 noeta2 ⊢ A ⊆ No ∧ A ∈ V ∧ B ⊆ No ∧ B ∈ V ∧ ∀ p ∈ A ∀ q ∈ B p < s q → ∃ y ∈ No ∀ p ∈ A p < s y ∧ ∀ q ∈ B y < s q ∧ bday ⁡ y ⊆ suc ⁡ ⋃ bday A ∪ B
7 1 2 3 4 5 6 syl221anc ⊢ A ≪ s B → ∃ y ∈ No ∀ p ∈ A p < s y ∧ ∀ q ∈ B y < s q ∧ bday ⁡ y ⊆ suc ⁡ ⋃ bday A ∪ B
8 3simpa ⊢ ∀ p ∈ A p < s y ∧ ∀ q ∈ B y < s q ∧ bday ⁡ y ⊆ suc ⁡ ⋃ bday A ∪ B → ∀ p ∈ A p < s y ∧ ∀ q ∈ B y < s q
9 2 ad2antrr ⊢ A ≪ s B ∧ y ∈ No ∧ ∀ p ∈ A p < s y → A ∈ V
10 vsnex ⊢ y ∈ V
11 9 10 jctir ⊢ A ≪ s B ∧ y ∈ No ∧ ∀ p ∈ A p < s y → A ∈ V ∧ y ∈ V
12 1 ad2antrr ⊢ A ≪ s B ∧ y ∈ No ∧ ∀ p ∈ A p < s y → A ⊆ No
13 snssi ⊢ y ∈ No → y ⊆ No
14 13 adantl ⊢ A ≪ s B ∧ y ∈ No → y ⊆ No
15 14 adantr ⊢ A ≪ s B ∧ y ∈ No ∧ ∀ p ∈ A p < s y → y ⊆ No
16 vex ⊢ y ∈ V
17 breq2 ⊢ q = y → p < s q ↔ p < s y
18 16 17 ralsn ⊢ ∀ q ∈ y p < s q ↔ p < s y
19 18 ralbii ⊢ ∀ p ∈ A ∀ q ∈ y p < s q ↔ ∀ p ∈ A p < s y
20 19 bilanri ⊢ A ≪ s B ∧ y ∈ No ∧ ∀ p ∈ A p < s y → ∀ p ∈ A ∀ q ∈ y p < s q
21 12 15 20 3jca ⊢ A ≪ s B ∧ y ∈ No ∧ ∀ p ∈ A p < s y → A ⊆ No ∧ y ⊆ No ∧ ∀ p ∈ A ∀ q ∈ y p < s q
22 brslts ⊢ A ≪ s y ↔ A ∈ V ∧ y ∈ V ∧ A ⊆ No ∧ y ⊆ No ∧ ∀ p ∈ A ∀ q ∈ y p < s q
23 11 21 22 sylanbrc ⊢ A ≪ s B ∧ y ∈ No ∧ ∀ p ∈ A p < s y → A ≪ s y
24 23 ex ⊢ A ≪ s B ∧ y ∈ No → ∀ p ∈ A p < s y → A ≪ s y
25 4 ad2antrr ⊢ A ≪ s B ∧ y ∈ No ∧ ∀ q ∈ B y < s q → B ∈ V
26 25 10 jctil ⊢ A ≪ s B ∧ y ∈ No ∧ ∀ q ∈ B y < s q → y ∈ V ∧ B ∈ V
27 14 adantr ⊢ A ≪ s B ∧ y ∈ No ∧ ∀ q ∈ B y < s q → y ⊆ No
28 3 ad2antrr ⊢ A ≪ s B ∧ y ∈ No ∧ ∀ q ∈ B y < s q → B ⊆ No
29 ralcom ⊢ ∀ p ∈ y ∀ q ∈ B p < s q ↔ ∀ q ∈ B ∀ p ∈ y p < s q
30 breq1 ⊢ p = y → p < s q ↔ y < s q
31 16 30 ralsn ⊢ ∀ p ∈ y p < s q ↔ y < s q
32 31 ralbii ⊢ ∀ q ∈ B ∀ p ∈ y p < s q ↔ ∀ q ∈ B y < s q
33 29 32 sylbbr ⊢ ∀ q ∈ B y < s q → ∀ p ∈ y ∀ q ∈ B p < s q
34 33 adantl ⊢ A ≪ s B ∧ y ∈ No ∧ ∀ q ∈ B y < s q → ∀ p ∈ y ∀ q ∈ B p < s q
35 27 28 34 3jca ⊢ A ≪ s B ∧ y ∈ No ∧ ∀ q ∈ B y < s q → y ⊆ No ∧ B ⊆ No ∧ ∀ p ∈ y ∀ q ∈ B p < s q
36 brslts ⊢ y ≪ s B ↔ y ∈ V ∧ B ∈ V ∧ y ⊆ No ∧ B ⊆ No ∧ ∀ p ∈ y ∀ q ∈ B p < s q
37 26 35 36 sylanbrc ⊢ A ≪ s B ∧ y ∈ No ∧ ∀ q ∈ B y < s q → y ≪ s B
38 37 ex ⊢ A ≪ s B ∧ y ∈ No → ∀ q ∈ B y < s q → y ≪ s B
39 24 38 anim12d ⊢ A ≪ s B ∧ y ∈ No → ∀ p ∈ A p < s y ∧ ∀ q ∈ B y < s q → A ≪ s y ∧ y ≪ s B
40 8 39 syl5 ⊢ A ≪ s B ∧ y ∈ No → ∀ p ∈ A p < s y ∧ ∀ q ∈ B y < s q ∧ bday ⁡ y ⊆ suc ⁡ ⋃ bday A ∪ B → A ≪ s y ∧ y ≪ s B
41 40 reximdva ⊢ A ≪ s B → ∃ y ∈ No ∀ p ∈ A p < s y ∧ ∀ q ∈ B y < s q ∧ bday ⁡ y ⊆ suc ⁡ ⋃ bday A ∪ B → ∃ y ∈ No A ≪ s y ∧ y ≪ s B
42 7 41 mpd ⊢ A ≪ s B → ∃ y ∈ No A ≪ s y ∧ y ≪ s B
43 rabn0 ⊢ y ∈ No | A ≪ s y ∧ y ≪ s B ≠ ∅ ↔ ∃ y ∈ No A ≪ s y ∧ y ≪ s B
44 42 43 sylibr ⊢ A ≪ s B → y ∈ No | A ≪ s y ∧ y ≪ s B ≠ ∅
45 ssrab2 ⊢ y ∈ No | A ≪ s y ∧ y ≪ s B ⊆ No
46 45 a1i ⊢ A ≪ s B → y ∈ No | A ≪ s y ∧ y ≪ s B ⊆ No
47 simplr3 ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → r ∈ No
48 2 ad2antrr ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → A ∈ V
49 vsnex ⊢ r ∈ V
50 48 49 jctir ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → A ∈ V ∧ r ∈ V
51 1 ad2antrr ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → A ⊆ No
52 47 snssd ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → r ⊆ No
53 51 sselda ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q ∧ x ∈ A → x ∈ No
54 simplr1 ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → p ∈ No
55 54 adantr ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q ∧ x ∈ A → p ∈ No
56 47 adantr ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q ∧ x ∈ A → r ∈ No
57 simplll ⊢ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → A ≪ s p
58 57 adantl ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → A ≪ s p
59 sltssep ⊢ A ≪ s p → ∀ x ∈ A ∀ y ∈ p x < s y
60 58 59 syl ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → ∀ x ∈ A ∀ y ∈ p x < s y
61 60 r19.21bi ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q ∧ x ∈ A → ∀ y ∈ p x < s y
62 vex ⊢ p ∈ V
63 breq2 ⊢ y = p → x < s y ↔ x < s p
64 62 63 ralsn ⊢ ∀ y ∈ p x < s y ↔ x < s p
65 61 64 sylib ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q ∧ x ∈ A → x < s p
66 simprrl ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → p < s r
67 66 adantr ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q ∧ x ∈ A → p < s r
68 53 55 56 65 67 ltstrd ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q ∧ x ∈ A → x < s r
69 vex ⊢ r ∈ V
70 breq2 ⊢ y = r → x < s y ↔ x < s r
71 69 70 ralsn ⊢ ∀ y ∈ r x < s y ↔ x < s r
72 68 71 sylibr ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q ∧ x ∈ A → ∀ y ∈ r x < s y
73 72 ralrimiva ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → ∀ x ∈ A ∀ y ∈ r x < s y
74 51 52 73 3jca ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → A ⊆ No ∧ r ⊆ No ∧ ∀ x ∈ A ∀ y ∈ r x < s y
75 brslts ⊢ A ≪ s r ↔ A ∈ V ∧ r ∈ V ∧ A ⊆ No ∧ r ⊆ No ∧ ∀ x ∈ A ∀ y ∈ r x < s y
76 50 74 75 sylanbrc ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → A ≪ s r
77 4 ad2antrr ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → B ∈ V
78 77 49 jctil ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → r ∈ V ∧ B ∈ V
79 3 ad2antrr ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → B ⊆ No
80 47 adantr ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q ∧ y ∈ B → r ∈ No
81 simplr2 ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → q ∈ No
82 81 adantr ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q ∧ y ∈ B → q ∈ No
83 79 sselda ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q ∧ y ∈ B → y ∈ No
84 simprrr ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → r < s q
85 84 adantr ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q ∧ y ∈ B → r < s q
86 simplrr ⊢ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → q ≪ s B
87 86 adantl ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → q ≪ s B
88 sltssep ⊢ q ≪ s B → ∀ x ∈ q ∀ y ∈ B x < s y
89 87 88 syl ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → ∀ x ∈ q ∀ y ∈ B x < s y
90 vex ⊢ q ∈ V
91 breq1 ⊢ x = q → x < s y ↔ q < s y
92 91 ralbidv ⊢ x = q → ∀ y ∈ B x < s y ↔ ∀ y ∈ B q < s y
93 90 92 ralsn ⊢ ∀ x ∈ q ∀ y ∈ B x < s y ↔ ∀ y ∈ B q < s y
94 89 93 sylib ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → ∀ y ∈ B q < s y
95 94 r19.21bi ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q ∧ y ∈ B → q < s y
96 80 82 83 85 95 ltstrd ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q ∧ y ∈ B → r < s y
97 96 ralrimiva ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → ∀ y ∈ B r < s y
98 breq1 ⊢ x = r → x < s y ↔ r < s y
99 98 ralbidv ⊢ x = r → ∀ y ∈ B x < s y ↔ ∀ y ∈ B r < s y
100 69 99 ralsn ⊢ ∀ x ∈ r ∀ y ∈ B x < s y ↔ ∀ y ∈ B r < s y
101 97 100 sylibr ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → ∀ x ∈ r ∀ y ∈ B x < s y
102 52 79 101 3jca ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → r ⊆ No ∧ B ⊆ No ∧ ∀ x ∈ r ∀ y ∈ B x < s y
103 brslts ⊢ r ≪ s B ↔ r ∈ V ∧ B ∈ V ∧ r ⊆ No ∧ B ⊆ No ∧ ∀ x ∈ r ∀ y ∈ B x < s y
104 78 102 103 sylanbrc ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → r ≪ s B
105 47 76 104 jca32 ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No ∧ A ≪ s p ∧ p ≪ s B ∧ A ≪ s q ∧ q ≪ s B ∧ p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B
106 105 exp44 ⊢ A ≪ s B ∧ p ∈ No ∧ q ∈ No ∧ r ∈ No → A ≪ s p ∧ p ≪ s B → A ≪ s q ∧ q ≪ s B → p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B
107 106 ralrimivvva ⊢ A ≪ s B → ∀ p ∈ No ∀ q ∈ No ∀ r ∈ No A ≪ s p ∧ p ≪ s B → A ≪ s q ∧ q ≪ s B → p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B
108 sneq ⊢ y = p → y = p
109 108 breq2d ⊢ y = p → A ≪ s y ↔ A ≪ s p
110 108 breq1d ⊢ y = p → y ≪ s B ↔ p ≪ s B
111 109 110 anbi12d ⊢ y = p → A ≪ s y ∧ y ≪ s B ↔ A ≪ s p ∧ p ≪ s B
112 111 ralrab ⊢ ∀ p ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ∀ q ∈ No ∀ r ∈ No A ≪ s q ∧ q ≪ s B → p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B ↔ ∀ p ∈ No A ≪ s p ∧ p ≪ s B → ∀ q ∈ No ∀ r ∈ No A ≪ s q ∧ q ≪ s B → p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B
113 sneq ⊢ y = q → y = q
114 113 breq2d ⊢ y = q → A ≪ s y ↔ A ≪ s q
115 113 breq1d ⊢ y = q → y ≪ s B ↔ q ≪ s B
116 114 115 anbi12d ⊢ y = q → A ≪ s y ∧ y ≪ s B ↔ A ≪ s q ∧ q ≪ s B
117 116 ralrab ⊢ ∀ q ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ∀ r ∈ No p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B ↔ ∀ q ∈ No A ≪ s q ∧ q ≪ s B → ∀ r ∈ No p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B
118 sneq ⊢ y = r → y = r
119 118 breq2d ⊢ y = r → A ≪ s y ↔ A ≪ s r
120 118 breq1d ⊢ y = r → y ≪ s B ↔ r ≪ s B
121 119 120 anbi12d ⊢ y = r → A ≪ s y ∧ y ≪ s B ↔ A ≪ s r ∧ r ≪ s B
122 121 elrab ⊢ r ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ↔ r ∈ No ∧ A ≪ s r ∧ r ≪ s B
123 122 imbi2i ⊢ p < s r ∧ r < s q → r ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ↔ p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B
124 123 ralbii ⊢ ∀ r ∈ No p < s r ∧ r < s q → r ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ↔ ∀ r ∈ No p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B
125 124 ralbii ⊢ ∀ q ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ∀ r ∈ No p < s r ∧ r < s q → r ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ↔ ∀ q ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ∀ r ∈ No p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B
126 r19.21v ⊢ ∀ r ∈ No A ≪ s q ∧ q ≪ s B → p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B ↔ A ≪ s q ∧ q ≪ s B → ∀ r ∈ No p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B
127 126 ralbii ⊢ ∀ q ∈ No ∀ r ∈ No A ≪ s q ∧ q ≪ s B → p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B ↔ ∀ q ∈ No A ≪ s q ∧ q ≪ s B → ∀ r ∈ No p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B
128 117 125 127 3bitr4i ⊢ ∀ q ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ∀ r ∈ No p < s r ∧ r < s q → r ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ↔ ∀ q ∈ No ∀ r ∈ No A ≪ s q ∧ q ≪ s B → p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B
129 128 ralbii ⊢ ∀ p ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ∀ q ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ∀ r ∈ No p < s r ∧ r < s q → r ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ↔ ∀ p ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ∀ q ∈ No ∀ r ∈ No A ≪ s q ∧ q ≪ s B → p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B
130 r19.21v ⊢ ∀ r ∈ No A ≪ s p ∧ p ≪ s B → A ≪ s q ∧ q ≪ s B → p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B ↔ A ≪ s p ∧ p ≪ s B → ∀ r ∈ No A ≪ s q ∧ q ≪ s B → p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B
131 130 ralbii ⊢ ∀ q ∈ No ∀ r ∈ No A ≪ s p ∧ p ≪ s B → A ≪ s q ∧ q ≪ s B → p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B ↔ ∀ q ∈ No A ≪ s p ∧ p ≪ s B → ∀ r ∈ No A ≪ s q ∧ q ≪ s B → p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B
132 r19.21v ⊢ ∀ q ∈ No A ≪ s p ∧ p ≪ s B → ∀ r ∈ No A ≪ s q ∧ q ≪ s B → p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B ↔ A ≪ s p ∧ p ≪ s B → ∀ q ∈ No ∀ r ∈ No A ≪ s q ∧ q ≪ s B → p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B
133 131 132 bitri ⊢ ∀ q ∈ No ∀ r ∈ No A ≪ s p ∧ p ≪ s B → A ≪ s q ∧ q ≪ s B → p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B ↔ A ≪ s p ∧ p ≪ s B → ∀ q ∈ No ∀ r ∈ No A ≪ s q ∧ q ≪ s B → p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B
134 133 ralbii ⊢ ∀ p ∈ No ∀ q ∈ No ∀ r ∈ No A ≪ s p ∧ p ≪ s B → A ≪ s q ∧ q ≪ s B → p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B ↔ ∀ p ∈ No A ≪ s p ∧ p ≪ s B → ∀ q ∈ No ∀ r ∈ No A ≪ s q ∧ q ≪ s B → p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B
135 112 129 134 3bitr4i ⊢ ∀ p ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ∀ q ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ∀ r ∈ No p < s r ∧ r < s q → r ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ↔ ∀ p ∈ No ∀ q ∈ No ∀ r ∈ No A ≪ s p ∧ p ≪ s B → A ≪ s q ∧ q ≪ s B → p < s r ∧ r < s q → r ∈ No ∧ A ≪ s r ∧ r ≪ s B
136 107 135 sylibr ⊢ A ≪ s B → ∀ p ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ∀ q ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ∀ r ∈ No p < s r ∧ r < s q → r ∈ y ∈ No | A ≪ s y ∧ y ≪ s B
137 nocvxmin ⊢ y ∈ No | A ≪ s y ∧ y ≪ s B ≠ ∅ ∧ y ∈ No | A ≪ s y ∧ y ≪ s B ⊆ No ∧ ∀ p ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ∀ q ∈ y ∈ No | A ≪ s y ∧ y ≪ s B ∀ r ∈ No p < s r ∧ r < s q → r ∈ y ∈ No | A ≪ s y ∧ y ≪ s B → ∃! x ∈ y ∈ No | A ≪ s y ∧ y ≪ s B bday ⁡ x = ⋂ bday y ∈ No | A ≪ s y ∧ y ≪ s B
138 44 46 136 137 syl3anc ⊢ A ≪ s B → ∃! x ∈ y ∈ No | A ≪ s y ∧ y ≪ s B bday ⁡ x = ⋂ bday y ∈ No | A ≪ s y ∧ y ≪ s B