| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | bdayelon 27821 | . . . 4
⊢ ( bday ‘𝐴) ∈ On | 
| 2 |  | bdayelon 27821 | . . . 4
⊢ ( bday ‘𝐵) ∈ On | 
| 3 | 1, 2 | onun2i 6506 | . . 3
⊢ (( bday ‘𝐴) ∪ ( bday
‘𝐵)) ∈
On | 
| 4 |  | risset 3233 | . . 3
⊢ ((( bday ‘𝐴) ∪ ( bday
‘𝐵)) ∈ On
↔ ∃𝑎 ∈ On
𝑎 = (( bday ‘𝐴) ∪ ( bday
‘𝐵))) | 
| 5 | 3, 4 | mpbi 230 | . 2
⊢
∃𝑎 ∈ On
𝑎 = (( bday ‘𝐴) ∪ ( bday
‘𝐵)) | 
| 6 |  | eqeq1 2741 | . . . . . . . . 9
⊢ (𝑎 = 𝑏 → (𝑎 = (( bday
‘𝑝) ∪
( bday ‘𝑞)) ↔ 𝑏 = (( bday
‘𝑝) ∪
( bday ‘𝑞)))) | 
| 7 | 6 | imbi1d 341 | . . . . . . . 8
⊢ (𝑎 = 𝑏 → ((𝑎 = (( bday
‘𝑝) ∪
( bday ‘𝑞)) → (( -us ‘𝑝) ∈ 
No  ∧ (𝑝 <s
𝑞 → ( -us
‘𝑞) <s (
-us ‘𝑝))))
↔ (𝑏 = (( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑝)
∈  No  ∧ (𝑝 <s 𝑞 → ( -us ‘𝑞) <s ( -us
‘𝑝)))))) | 
| 8 | 7 | 2ralbidv 3221 | . . . . . . 7
⊢ (𝑎 = 𝑏 → (∀𝑝 ∈  No 
∀𝑞 ∈  No  (𝑎 = (( bday
‘𝑝) ∪
( bday ‘𝑞)) → (( -us ‘𝑝) ∈ 
No  ∧ (𝑝 <s
𝑞 → ( -us
‘𝑞) <s (
-us ‘𝑝))))
↔ ∀𝑝 ∈
 No  ∀𝑞 ∈  No 
(𝑏 = (( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑝)
∈  No  ∧ (𝑝 <s 𝑞 → ( -us ‘𝑞) <s ( -us
‘𝑝)))))) | 
| 9 |  | fveq2 6906 | . . . . . . . . . . 11
⊢ (𝑝 = 𝑥 → ( bday
‘𝑝) = ( bday ‘𝑥)) | 
| 10 | 9 | uneq1d 4167 | . . . . . . . . . 10
⊢ (𝑝 = 𝑥 → (( bday
‘𝑝) ∪
( bday ‘𝑞)) = (( bday
‘𝑥) ∪
( bday ‘𝑞))) | 
| 11 | 10 | eqeq2d 2748 | . . . . . . . . 9
⊢ (𝑝 = 𝑥 → (𝑏 = (( bday
‘𝑝) ∪
( bday ‘𝑞)) ↔ 𝑏 = (( bday
‘𝑥) ∪
( bday ‘𝑞)))) | 
| 12 |  | fveq2 6906 | . . . . . . . . . . 11
⊢ (𝑝 = 𝑥 → ( -us ‘𝑝) = ( -us
‘𝑥)) | 
| 13 | 12 | eleq1d 2826 | . . . . . . . . . 10
⊢ (𝑝 = 𝑥 → (( -us ‘𝑝) ∈ 
No  ↔ ( -us ‘𝑥) ∈  No
)) | 
| 14 |  | breq1 5146 | . . . . . . . . . . 11
⊢ (𝑝 = 𝑥 → (𝑝 <s 𝑞 ↔ 𝑥 <s 𝑞)) | 
| 15 | 12 | breq2d 5155 | . . . . . . . . . . 11
⊢ (𝑝 = 𝑥 → (( -us ‘𝑞) <s ( -us
‘𝑝) ↔ (
-us ‘𝑞)
<s ( -us ‘𝑥))) | 
| 16 | 14, 15 | imbi12d 344 | . . . . . . . . . 10
⊢ (𝑝 = 𝑥 → ((𝑝 <s 𝑞 → ( -us ‘𝑞) <s ( -us
‘𝑝)) ↔ (𝑥 <s 𝑞 → ( -us ‘𝑞) <s ( -us
‘𝑥)))) | 
| 17 | 13, 16 | anbi12d 632 | . . . . . . . . 9
⊢ (𝑝 = 𝑥 → ((( -us ‘𝑝) ∈ 
No  ∧ (𝑝 <s
𝑞 → ( -us
‘𝑞) <s (
-us ‘𝑝)))
↔ (( -us ‘𝑥) ∈  No 
∧ (𝑥 <s 𝑞 → ( -us
‘𝑞) <s (
-us ‘𝑥))))) | 
| 18 | 11, 17 | imbi12d 344 | . . . . . . . 8
⊢ (𝑝 = 𝑥 → ((𝑏 = (( bday
‘𝑝) ∪
( bday ‘𝑞)) → (( -us ‘𝑝) ∈ 
No  ∧ (𝑝 <s
𝑞 → ( -us
‘𝑞) <s (
-us ‘𝑝))))
↔ (𝑏 = (( bday ‘𝑥) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑞 → ( -us ‘𝑞) <s ( -us
‘𝑥)))))) | 
| 19 |  | fveq2 6906 | . . . . . . . . . . 11
⊢ (𝑞 = 𝑦 → ( bday
‘𝑞) = ( bday ‘𝑦)) | 
| 20 | 19 | uneq2d 4168 | . . . . . . . . . 10
⊢ (𝑞 = 𝑦 → (( bday
‘𝑥) ∪
( bday ‘𝑞)) = (( bday
‘𝑥) ∪
( bday ‘𝑦))) | 
| 21 | 20 | eqeq2d 2748 | . . . . . . . . 9
⊢ (𝑞 = 𝑦 → (𝑏 = (( bday
‘𝑥) ∪
( bday ‘𝑞)) ↔ 𝑏 = (( bday
‘𝑥) ∪
( bday ‘𝑦)))) | 
| 22 |  | breq2 5147 | . . . . . . . . . . 11
⊢ (𝑞 = 𝑦 → (𝑥 <s 𝑞 ↔ 𝑥 <s 𝑦)) | 
| 23 |  | fveq2 6906 | . . . . . . . . . . . 12
⊢ (𝑞 = 𝑦 → ( -us ‘𝑞) = ( -us
‘𝑦)) | 
| 24 | 23 | breq1d 5153 | . . . . . . . . . . 11
⊢ (𝑞 = 𝑦 → (( -us ‘𝑞) <s ( -us
‘𝑥) ↔ (
-us ‘𝑦)
<s ( -us ‘𝑥))) | 
| 25 | 22, 24 | imbi12d 344 | . . . . . . . . . 10
⊢ (𝑞 = 𝑦 → ((𝑥 <s 𝑞 → ( -us ‘𝑞) <s ( -us
‘𝑥)) ↔ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥)))) | 
| 26 | 25 | anbi2d 630 | . . . . . . . . 9
⊢ (𝑞 = 𝑦 → ((( -us ‘𝑥) ∈ 
No  ∧ (𝑥 <s
𝑞 → ( -us
‘𝑞) <s (
-us ‘𝑥)))
↔ (( -us ‘𝑥) ∈  No 
∧ (𝑥 <s 𝑦 → ( -us
‘𝑦) <s (
-us ‘𝑥))))) | 
| 27 | 21, 26 | imbi12d 344 | . . . . . . . 8
⊢ (𝑞 = 𝑦 → ((𝑏 = (( bday
‘𝑥) ∪
( bday ‘𝑞)) → (( -us ‘𝑥) ∈ 
No  ∧ (𝑥 <s
𝑞 → ( -us
‘𝑞) <s (
-us ‘𝑥))))
↔ (𝑏 = (( bday ‘𝑥) ∪ ( bday
‘𝑦)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥)))))) | 
| 28 | 18, 27 | cbvral2vw 3241 | . . . . . . 7
⊢
(∀𝑝 ∈
 No  ∀𝑞 ∈  No 
(𝑏 = (( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑝)
∈  No  ∧ (𝑝 <s 𝑞 → ( -us ‘𝑞) <s ( -us
‘𝑝)))) ↔
∀𝑥 ∈  No  ∀𝑦 ∈  No 
(𝑏 = (( bday ‘𝑥) ∪ ( bday
‘𝑦)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥))))) | 
| 29 | 8, 28 | bitrdi 287 | . . . . . 6
⊢ (𝑎 = 𝑏 → (∀𝑝 ∈  No 
∀𝑞 ∈  No  (𝑎 = (( bday
‘𝑝) ∪
( bday ‘𝑞)) → (( -us ‘𝑝) ∈ 
No  ∧ (𝑝 <s
𝑞 → ( -us
‘𝑞) <s (
-us ‘𝑝))))
↔ ∀𝑥 ∈
 No  ∀𝑦 ∈  No 
(𝑏 = (( bday ‘𝑥) ∪ ( bday
‘𝑦)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥)))))) | 
| 30 |  | raleq 3323 | . . . . . . . . . . 11
⊢ (𝑎 = (( bday
‘𝑝) ∪
( bday ‘𝑞)) → (∀𝑏 ∈ 𝑎 ∀𝑥 ∈  No 
∀𝑦 ∈  No  (𝑏 = (( bday
‘𝑥) ∪
( bday ‘𝑦)) → (( -us ‘𝑥) ∈ 
No  ∧ (𝑥 <s
𝑦 → ( -us
‘𝑦) <s (
-us ‘𝑥))))
↔ ∀𝑏 ∈
(( bday ‘𝑝) ∪ ( bday
‘𝑞))∀𝑥 ∈  No 
∀𝑦 ∈  No  (𝑏 = (( bday
‘𝑥) ∪
( bday ‘𝑦)) → (( -us ‘𝑥) ∈ 
No  ∧ (𝑥 <s
𝑦 → ( -us
‘𝑦) <s (
-us ‘𝑥)))))) | 
| 31 |  | ralrot3 3293 | . . . . . . . . . . . 12
⊢
(∀𝑥 ∈
 No  ∀𝑦 ∈  No 
∀𝑏 ∈ (( bday ‘𝑝) ∪ ( bday
‘𝑞))(𝑏 = (( bday
‘𝑥) ∪
( bday ‘𝑦)) → (( -us ‘𝑥) ∈ 
No  ∧ (𝑥 <s
𝑦 → ( -us
‘𝑦) <s (
-us ‘𝑥))))
↔ ∀𝑏 ∈
(( bday ‘𝑝) ∪ ( bday
‘𝑞))∀𝑥 ∈  No 
∀𝑦 ∈  No  (𝑏 = (( bday
‘𝑥) ∪
( bday ‘𝑦)) → (( -us ‘𝑥) ∈ 
No  ∧ (𝑥 <s
𝑦 → ( -us
‘𝑦) <s (
-us ‘𝑥))))) | 
| 32 |  | r19.23v 3183 | . . . . . . . . . . . . . 14
⊢
(∀𝑏 ∈
(( bday ‘𝑝) ∪ ( bday
‘𝑞))(𝑏 = (( bday
‘𝑥) ∪
( bday ‘𝑦)) → (( -us ‘𝑥) ∈ 
No  ∧ (𝑥 <s
𝑦 → ( -us
‘𝑦) <s (
-us ‘𝑥))))
↔ (∃𝑏 ∈
(( bday ‘𝑝) ∪ ( bday
‘𝑞))𝑏 = (( bday
‘𝑥) ∪
( bday ‘𝑦)) → (( -us ‘𝑥) ∈ 
No  ∧ (𝑥 <s
𝑦 → ( -us
‘𝑦) <s (
-us ‘𝑥))))) | 
| 33 |  | risset 3233 | . . . . . . . . . . . . . . 15
⊢ ((( bday ‘𝑥) ∪ ( bday
‘𝑦)) ∈
(( bday ‘𝑝) ∪ ( bday
‘𝑞)) ↔
∃𝑏 ∈ (( bday ‘𝑝) ∪ ( bday
‘𝑞))𝑏 = (( bday
‘𝑥) ∪
( bday ‘𝑦))) | 
| 34 | 33 | imbi1i 349 | . . . . . . . . . . . . . 14
⊢ (((( bday ‘𝑥) ∪ ( bday
‘𝑦)) ∈
(( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥)))) ↔
(∃𝑏 ∈ (( bday ‘𝑝) ∪ ( bday
‘𝑞))𝑏 = (( bday
‘𝑥) ∪
( bday ‘𝑦)) → (( -us ‘𝑥) ∈ 
No  ∧ (𝑥 <s
𝑦 → ( -us
‘𝑦) <s (
-us ‘𝑥))))) | 
| 35 | 32, 34 | bitr4i 278 | . . . . . . . . . . . . 13
⊢
(∀𝑏 ∈
(( bday ‘𝑝) ∪ ( bday
‘𝑞))(𝑏 = (( bday
‘𝑥) ∪
( bday ‘𝑦)) → (( -us ‘𝑥) ∈ 
No  ∧ (𝑥 <s
𝑦 → ( -us
‘𝑦) <s (
-us ‘𝑥))))
↔ ((( bday ‘𝑥) ∪ ( bday
‘𝑦)) ∈
(( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥))))) | 
| 36 | 35 | 2ralbii 3128 | . . . . . . . . . . . 12
⊢
(∀𝑥 ∈
 No  ∀𝑦 ∈  No 
∀𝑏 ∈ (( bday ‘𝑝) ∪ ( bday
‘𝑞))(𝑏 = (( bday
‘𝑥) ∪
( bday ‘𝑦)) → (( -us ‘𝑥) ∈ 
No  ∧ (𝑥 <s
𝑦 → ( -us
‘𝑦) <s (
-us ‘𝑥))))
↔ ∀𝑥 ∈
 No  ∀𝑦 ∈  No 
((( bday ‘𝑥) ∪ ( bday
‘𝑦)) ∈
(( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥))))) | 
| 37 | 31, 36 | bitr3i 277 | . . . . . . . . . . 11
⊢
(∀𝑏 ∈
(( bday ‘𝑝) ∪ ( bday
‘𝑞))∀𝑥 ∈  No 
∀𝑦 ∈  No  (𝑏 = (( bday
‘𝑥) ∪
( bday ‘𝑦)) → (( -us ‘𝑥) ∈ 
No  ∧ (𝑥 <s
𝑦 → ( -us
‘𝑦) <s (
-us ‘𝑥))))
↔ ∀𝑥 ∈
 No  ∀𝑦 ∈  No 
((( bday ‘𝑥) ∪ ( bday
‘𝑦)) ∈
(( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥))))) | 
| 38 | 30, 37 | bitrdi 287 | . . . . . . . . . 10
⊢ (𝑎 = (( bday
‘𝑝) ∪
( bday ‘𝑞)) → (∀𝑏 ∈ 𝑎 ∀𝑥 ∈  No 
∀𝑦 ∈  No  (𝑏 = (( bday
‘𝑥) ∪
( bday ‘𝑦)) → (( -us ‘𝑥) ∈ 
No  ∧ (𝑥 <s
𝑦 → ( -us
‘𝑦) <s (
-us ‘𝑥))))
↔ ∀𝑥 ∈
 No  ∀𝑦 ∈  No 
((( bday ‘𝑥) ∪ ( bday
‘𝑦)) ∈
(( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥)))))) | 
| 39 |  | simpr 484 | . . . . . . . . . . . . . 14
⊢ (((𝑝 ∈ 
No  ∧ 𝑞 ∈
 No ) ∧ ∀𝑥 ∈  No 
∀𝑦 ∈  No  ((( bday ‘𝑥) ∪ (
bday ‘𝑦))
∈ (( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥))))) →
∀𝑥 ∈  No  ∀𝑦 ∈  No 
((( bday ‘𝑥) ∪ ( bday
‘𝑦)) ∈
(( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥))))) | 
| 40 |  | simpll 767 | . . . . . . . . . . . . . 14
⊢ (((𝑝 ∈ 
No  ∧ 𝑞 ∈
 No ) ∧ ∀𝑥 ∈  No 
∀𝑦 ∈  No  ((( bday ‘𝑥) ∪ (
bday ‘𝑦))
∈ (( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥))))) → 𝑝 ∈ 
No ) | 
| 41 | 39, 40 | negsproplem3 28062 | . . . . . . . . . . . . 13
⊢ (((𝑝 ∈ 
No  ∧ 𝑞 ∈
 No ) ∧ ∀𝑥 ∈  No 
∀𝑦 ∈  No  ((( bday ‘𝑥) ∪ (
bday ‘𝑦))
∈ (( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥))))) → ((
-us ‘𝑝)
∈  No  ∧ ( -us “ ( R
‘𝑝)) <<s {(
-us ‘𝑝)}
∧ {( -us ‘𝑝)} <<s ( -us “ ( L
‘𝑝)))) | 
| 42 | 41 | simp1d 1143 | . . . . . . . . . . . 12
⊢ (((𝑝 ∈ 
No  ∧ 𝑞 ∈
 No ) ∧ ∀𝑥 ∈  No 
∀𝑦 ∈  No  ((( bday ‘𝑥) ∪ (
bday ‘𝑦))
∈ (( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥))))) → (
-us ‘𝑝)
∈  No ) | 
| 43 |  | simplr 769 | . . . . . . . . . . . . . 14
⊢ ((((𝑝 ∈ 
No  ∧ 𝑞 ∈
 No ) ∧ ∀𝑥 ∈  No 
∀𝑦 ∈  No  ((( bday ‘𝑥) ∪ (
bday ‘𝑦))
∈ (( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥))))) ∧ 𝑝 <s 𝑞) → ∀𝑥 ∈  No 
∀𝑦 ∈  No  ((( bday ‘𝑥) ∪ (
bday ‘𝑦))
∈ (( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥))))) | 
| 44 |  | simplll 775 | . . . . . . . . . . . . . 14
⊢ ((((𝑝 ∈ 
No  ∧ 𝑞 ∈
 No ) ∧ ∀𝑥 ∈  No 
∀𝑦 ∈  No  ((( bday ‘𝑥) ∪ (
bday ‘𝑦))
∈ (( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥))))) ∧ 𝑝 <s 𝑞) → 𝑝 ∈  No
) | 
| 45 |  | simpllr 776 | . . . . . . . . . . . . . 14
⊢ ((((𝑝 ∈ 
No  ∧ 𝑞 ∈
 No ) ∧ ∀𝑥 ∈  No 
∀𝑦 ∈  No  ((( bday ‘𝑥) ∪ (
bday ‘𝑦))
∈ (( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥))))) ∧ 𝑝 <s 𝑞) → 𝑞 ∈  No
) | 
| 46 |  | simpr 484 | . . . . . . . . . . . . . 14
⊢ ((((𝑝 ∈ 
No  ∧ 𝑞 ∈
 No ) ∧ ∀𝑥 ∈  No 
∀𝑦 ∈  No  ((( bday ‘𝑥) ∪ (
bday ‘𝑦))
∈ (( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥))))) ∧ 𝑝 <s 𝑞) → 𝑝 <s 𝑞) | 
| 47 | 43, 44, 45, 46 | negsproplem7 28066 | . . . . . . . . . . . . 13
⊢ ((((𝑝 ∈ 
No  ∧ 𝑞 ∈
 No ) ∧ ∀𝑥 ∈  No 
∀𝑦 ∈  No  ((( bday ‘𝑥) ∪ (
bday ‘𝑦))
∈ (( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥))))) ∧ 𝑝 <s 𝑞) → ( -us ‘𝑞) <s ( -us
‘𝑝)) | 
| 48 | 47 | ex 412 | . . . . . . . . . . . 12
⊢ (((𝑝 ∈ 
No  ∧ 𝑞 ∈
 No ) ∧ ∀𝑥 ∈  No 
∀𝑦 ∈  No  ((( bday ‘𝑥) ∪ (
bday ‘𝑦))
∈ (( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥))))) → (𝑝 <s 𝑞 → ( -us ‘𝑞) <s ( -us
‘𝑝))) | 
| 49 | 42, 48 | jca 511 | . . . . . . . . . . 11
⊢ (((𝑝 ∈ 
No  ∧ 𝑞 ∈
 No ) ∧ ∀𝑥 ∈  No 
∀𝑦 ∈  No  ((( bday ‘𝑥) ∪ (
bday ‘𝑦))
∈ (( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥))))) → ((
-us ‘𝑝)
∈  No  ∧ (𝑝 <s 𝑞 → ( -us ‘𝑞) <s ( -us
‘𝑝)))) | 
| 50 | 49 | expcom 413 | . . . . . . . . . 10
⊢
(∀𝑥 ∈
 No  ∀𝑦 ∈  No 
((( bday ‘𝑥) ∪ ( bday
‘𝑦)) ∈
(( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑥)
∈  No  ∧ (𝑥 <s 𝑦 → ( -us ‘𝑦) <s ( -us
‘𝑥)))) → ((𝑝 ∈ 
No  ∧ 𝑞 ∈
 No ) → (( -us ‘𝑝) ∈ 
No  ∧ (𝑝 <s
𝑞 → ( -us
‘𝑞) <s (
-us ‘𝑝))))) | 
| 51 | 38, 50 | biimtrdi 253 | . . . . . . . . 9
⊢ (𝑎 = (( bday
‘𝑝) ∪
( bday ‘𝑞)) → (∀𝑏 ∈ 𝑎 ∀𝑥 ∈  No 
∀𝑦 ∈  No  (𝑏 = (( bday
‘𝑥) ∪
( bday ‘𝑦)) → (( -us ‘𝑥) ∈ 
No  ∧ (𝑥 <s
𝑦 → ( -us
‘𝑦) <s (
-us ‘𝑥))))
→ ((𝑝 ∈  No  ∧ 𝑞 ∈  No )
→ (( -us ‘𝑝) ∈  No 
∧ (𝑝 <s 𝑞 → ( -us
‘𝑞) <s (
-us ‘𝑝)))))) | 
| 52 | 51 | com3l 89 | . . . . . . . 8
⊢
(∀𝑏 ∈
𝑎 ∀𝑥 ∈ 
No  ∀𝑦 ∈
 No  (𝑏 = (( bday
‘𝑥) ∪
( bday ‘𝑦)) → (( -us ‘𝑥) ∈ 
No  ∧ (𝑥 <s
𝑦 → ( -us
‘𝑦) <s (
-us ‘𝑥))))
→ ((𝑝 ∈  No  ∧ 𝑞 ∈  No )
→ (𝑎 = (( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑝)
∈  No  ∧ (𝑝 <s 𝑞 → ( -us ‘𝑞) <s ( -us
‘𝑝)))))) | 
| 53 | 52 | ralrimivv 3200 | . . . . . . 7
⊢
(∀𝑏 ∈
𝑎 ∀𝑥 ∈ 
No  ∀𝑦 ∈
 No  (𝑏 = (( bday
‘𝑥) ∪
( bday ‘𝑦)) → (( -us ‘𝑥) ∈ 
No  ∧ (𝑥 <s
𝑦 → ( -us
‘𝑦) <s (
-us ‘𝑥))))
→ ∀𝑝 ∈
 No  ∀𝑞 ∈  No 
(𝑎 = (( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑝)
∈  No  ∧ (𝑝 <s 𝑞 → ( -us ‘𝑞) <s ( -us
‘𝑝))))) | 
| 54 | 53 | a1i 11 | . . . . . 6
⊢ (𝑎 ∈ On → (∀𝑏 ∈ 𝑎 ∀𝑥 ∈  No 
∀𝑦 ∈  No  (𝑏 = (( bday
‘𝑥) ∪
( bday ‘𝑦)) → (( -us ‘𝑥) ∈ 
No  ∧ (𝑥 <s
𝑦 → ( -us
‘𝑦) <s (
-us ‘𝑥))))
→ ∀𝑝 ∈
 No  ∀𝑞 ∈  No 
(𝑎 = (( bday ‘𝑝) ∪ ( bday
‘𝑞)) → ((
-us ‘𝑝)
∈  No  ∧ (𝑝 <s 𝑞 → ( -us ‘𝑞) <s ( -us
‘𝑝)))))) | 
| 55 | 29, 54 | tfis2 7878 | . . . . 5
⊢ (𝑎 ∈ On → ∀𝑝 ∈ 
No  ∀𝑞 ∈
 No  (𝑎 = (( bday
‘𝑝) ∪
( bday ‘𝑞)) → (( -us ‘𝑝) ∈ 
No  ∧ (𝑝 <s
𝑞 → ( -us
‘𝑞) <s (
-us ‘𝑝))))) | 
| 56 |  | fveq2 6906 | . . . . . . . . 9
⊢ (𝑝 = 𝐴 → ( bday
‘𝑝) = ( bday ‘𝐴)) | 
| 57 | 56 | uneq1d 4167 | . . . . . . . 8
⊢ (𝑝 = 𝐴 → (( bday
‘𝑝) ∪
( bday ‘𝑞)) = (( bday
‘𝐴) ∪
( bday ‘𝑞))) | 
| 58 | 57 | eqeq2d 2748 | . . . . . . 7
⊢ (𝑝 = 𝐴 → (𝑎 = (( bday
‘𝑝) ∪
( bday ‘𝑞)) ↔ 𝑎 = (( bday
‘𝐴) ∪
( bday ‘𝑞)))) | 
| 59 |  | fveq2 6906 | . . . . . . . . 9
⊢ (𝑝 = 𝐴 → ( -us ‘𝑝) = ( -us
‘𝐴)) | 
| 60 | 59 | eleq1d 2826 | . . . . . . . 8
⊢ (𝑝 = 𝐴 → (( -us ‘𝑝) ∈ 
No  ↔ ( -us ‘𝐴) ∈  No
)) | 
| 61 |  | breq1 5146 | . . . . . . . . 9
⊢ (𝑝 = 𝐴 → (𝑝 <s 𝑞 ↔ 𝐴 <s 𝑞)) | 
| 62 | 59 | breq2d 5155 | . . . . . . . . 9
⊢ (𝑝 = 𝐴 → (( -us ‘𝑞) <s ( -us
‘𝑝) ↔ (
-us ‘𝑞)
<s ( -us ‘𝐴))) | 
| 63 | 61, 62 | imbi12d 344 | . . . . . . . 8
⊢ (𝑝 = 𝐴 → ((𝑝 <s 𝑞 → ( -us ‘𝑞) <s ( -us
‘𝑝)) ↔ (𝐴 <s 𝑞 → ( -us ‘𝑞) <s ( -us
‘𝐴)))) | 
| 64 | 60, 63 | anbi12d 632 | . . . . . . 7
⊢ (𝑝 = 𝐴 → ((( -us ‘𝑝) ∈ 
No  ∧ (𝑝 <s
𝑞 → ( -us
‘𝑞) <s (
-us ‘𝑝)))
↔ (( -us ‘𝐴) ∈  No 
∧ (𝐴 <s 𝑞 → ( -us
‘𝑞) <s (
-us ‘𝐴))))) | 
| 65 | 58, 64 | imbi12d 344 | . . . . . 6
⊢ (𝑝 = 𝐴 → ((𝑎 = (( bday
‘𝑝) ∪
( bday ‘𝑞)) → (( -us ‘𝑝) ∈ 
No  ∧ (𝑝 <s
𝑞 → ( -us
‘𝑞) <s (
-us ‘𝑝))))
↔ (𝑎 = (( bday ‘𝐴) ∪ ( bday
‘𝑞)) → ((
-us ‘𝐴)
∈  No  ∧ (𝐴 <s 𝑞 → ( -us ‘𝑞) <s ( -us
‘𝐴)))))) | 
| 66 |  | fveq2 6906 | . . . . . . . . 9
⊢ (𝑞 = 𝐵 → ( bday
‘𝑞) = ( bday ‘𝐵)) | 
| 67 | 66 | uneq2d 4168 | . . . . . . . 8
⊢ (𝑞 = 𝐵 → (( bday
‘𝐴) ∪
( bday ‘𝑞)) = (( bday
‘𝐴) ∪
( bday ‘𝐵))) | 
| 68 | 67 | eqeq2d 2748 | . . . . . . 7
⊢ (𝑞 = 𝐵 → (𝑎 = (( bday
‘𝐴) ∪
( bday ‘𝑞)) ↔ 𝑎 = (( bday
‘𝐴) ∪
( bday ‘𝐵)))) | 
| 69 |  | breq2 5147 | . . . . . . . . 9
⊢ (𝑞 = 𝐵 → (𝐴 <s 𝑞 ↔ 𝐴 <s 𝐵)) | 
| 70 |  | fveq2 6906 | . . . . . . . . . 10
⊢ (𝑞 = 𝐵 → ( -us ‘𝑞) = ( -us
‘𝐵)) | 
| 71 | 70 | breq1d 5153 | . . . . . . . . 9
⊢ (𝑞 = 𝐵 → (( -us ‘𝑞) <s ( -us
‘𝐴) ↔ (
-us ‘𝐵)
<s ( -us ‘𝐴))) | 
| 72 | 69, 71 | imbi12d 344 | . . . . . . . 8
⊢ (𝑞 = 𝐵 → ((𝐴 <s 𝑞 → ( -us ‘𝑞) <s ( -us
‘𝐴)) ↔ (𝐴 <s 𝐵 → ( -us ‘𝐵) <s ( -us
‘𝐴)))) | 
| 73 | 72 | anbi2d 630 | . . . . . . 7
⊢ (𝑞 = 𝐵 → ((( -us ‘𝐴) ∈ 
No  ∧ (𝐴 <s
𝑞 → ( -us
‘𝑞) <s (
-us ‘𝐴)))
↔ (( -us ‘𝐴) ∈  No 
∧ (𝐴 <s 𝐵 → ( -us
‘𝐵) <s (
-us ‘𝐴))))) | 
| 74 | 68, 73 | imbi12d 344 | . . . . . 6
⊢ (𝑞 = 𝐵 → ((𝑎 = (( bday
‘𝐴) ∪
( bday ‘𝑞)) → (( -us ‘𝐴) ∈ 
No  ∧ (𝐴 <s
𝑞 → ( -us
‘𝑞) <s (
-us ‘𝐴))))
↔ (𝑎 = (( bday ‘𝐴) ∪ ( bday
‘𝐵)) → ((
-us ‘𝐴)
∈  No  ∧ (𝐴 <s 𝐵 → ( -us ‘𝐵) <s ( -us
‘𝐴)))))) | 
| 75 | 65, 74 | rspc2v 3633 | . . . . 5
⊢ ((𝐴 ∈ 
No  ∧ 𝐵 ∈
 No ) → (∀𝑝 ∈  No 
∀𝑞 ∈  No  (𝑎 = (( bday
‘𝑝) ∪
( bday ‘𝑞)) → (( -us ‘𝑝) ∈ 
No  ∧ (𝑝 <s
𝑞 → ( -us
‘𝑞) <s (
-us ‘𝑝))))
→ (𝑎 = (( bday ‘𝐴) ∪ ( bday
‘𝐵)) → ((
-us ‘𝐴)
∈  No  ∧ (𝐴 <s 𝐵 → ( -us ‘𝐵) <s ( -us
‘𝐴)))))) | 
| 76 | 55, 75 | syl5com 31 | . . . 4
⊢ (𝑎 ∈ On → ((𝐴 ∈ 
No  ∧ 𝐵 ∈
 No ) → (𝑎 = (( bday
‘𝐴) ∪
( bday ‘𝐵)) → (( -us ‘𝐴) ∈ 
No  ∧ (𝐴 <s
𝐵 → ( -us
‘𝐵) <s (
-us ‘𝐴)))))) | 
| 77 | 76 | com23 86 | . . 3
⊢ (𝑎 ∈ On → (𝑎 = (( bday
‘𝐴) ∪
( bday ‘𝐵)) → ((𝐴 ∈  No 
∧ 𝐵 ∈  No ) → (( -us ‘𝐴) ∈  No 
∧ (𝐴 <s 𝐵 → ( -us
‘𝐵) <s (
-us ‘𝐴)))))) | 
| 78 | 77 | rexlimiv 3148 | . 2
⊢
(∃𝑎 ∈ On
𝑎 = (( bday ‘𝐴) ∪ ( bday
‘𝐵)) →
((𝐴 ∈  No  ∧ 𝐵 ∈  No )
→ (( -us ‘𝐴) ∈  No 
∧ (𝐴 <s 𝐵 → ( -us
‘𝐵) <s (
-us ‘𝐴))))) | 
| 79 | 5, 78 | ax-mp 5 | 1
⊢ ((𝐴 ∈ 
No  ∧ 𝐵 ∈
 No ) → (( -us ‘𝐴) ∈ 
No  ∧ (𝐴 <s
𝐵 → ( -us
‘𝐵) <s (
-us ‘𝐴)))) |