| Step | Hyp | Ref
| Expression |
| 1 | | nsmallnq 11017 |
. . . 4
⊢ (𝐴 ∈ Q →
∃𝑥 𝑥 <Q 𝐴) |
| 2 | | abn0 4385 |
. . . 4
⊢ ({𝑥 ∣ 𝑥 <Q 𝐴} ≠ ∅ ↔
∃𝑥 𝑥 <Q 𝐴) |
| 3 | 1, 2 | sylibr 234 |
. . 3
⊢ (𝐴 ∈ Q →
{𝑥 ∣ 𝑥 <Q
𝐴} ≠
∅) |
| 4 | | 0pss 4447 |
. . 3
⊢ (∅
⊊ {𝑥 ∣ 𝑥 <Q
𝐴} ↔ {𝑥 ∣ 𝑥 <Q 𝐴} ≠ ∅) |
| 5 | 3, 4 | sylibr 234 |
. 2
⊢ (𝐴 ∈ Q →
∅ ⊊ {𝑥 ∣
𝑥
<Q 𝐴}) |
| 6 | | ltrelnq 10966 |
. . . . . 6
⊢
<Q ⊆ (Q ×
Q) |
| 7 | 6 | brel 5750 |
. . . . 5
⊢ (𝑥 <Q
𝐴 → (𝑥 ∈ Q ∧
𝐴 ∈
Q)) |
| 8 | 7 | simpld 494 |
. . . 4
⊢ (𝑥 <Q
𝐴 → 𝑥 ∈ Q) |
| 9 | 8 | abssi 4070 |
. . 3
⊢ {𝑥 ∣ 𝑥 <Q 𝐴} ⊆
Q |
| 10 | | ltsonq 11009 |
. . . . . 6
⊢
<Q Or Q |
| 11 | 10, 6 | soirri 6146 |
. . . . 5
⊢ ¬
𝐴
<Q 𝐴 |
| 12 | | breq1 5146 |
. . . . . 6
⊢ (𝑥 = 𝐴 → (𝑥 <Q 𝐴 ↔ 𝐴 <Q 𝐴)) |
| 13 | 12 | elabg 3676 |
. . . . 5
⊢ (𝐴 ∈ Q →
(𝐴 ∈ {𝑥 ∣ 𝑥 <Q 𝐴} ↔ 𝐴 <Q 𝐴)) |
| 14 | 11, 13 | mtbiri 327 |
. . . 4
⊢ (𝐴 ∈ Q →
¬ 𝐴 ∈ {𝑥 ∣ 𝑥 <Q 𝐴}) |
| 15 | 14 | ancli 548 |
. . 3
⊢ (𝐴 ∈ Q →
(𝐴 ∈ Q
∧ ¬ 𝐴 ∈ {𝑥 ∣ 𝑥 <Q 𝐴})) |
| 16 | | ssnelpss 4114 |
. . 3
⊢ ({𝑥 ∣ 𝑥 <Q 𝐴} ⊆ Q →
((𝐴 ∈ Q
∧ ¬ 𝐴 ∈ {𝑥 ∣ 𝑥 <Q 𝐴}) → {𝑥 ∣ 𝑥 <Q 𝐴} ⊊
Q)) |
| 17 | 9, 15, 16 | mpsyl 68 |
. 2
⊢ (𝐴 ∈ Q →
{𝑥 ∣ 𝑥 <Q
𝐴} ⊊
Q) |
| 18 | | vex 3484 |
. . . . 5
⊢ 𝑦 ∈ V |
| 19 | | breq1 5146 |
. . . . 5
⊢ (𝑥 = 𝑦 → (𝑥 <Q 𝐴 ↔ 𝑦 <Q 𝐴)) |
| 20 | 18, 19 | elab 3679 |
. . . 4
⊢ (𝑦 ∈ {𝑥 ∣ 𝑥 <Q 𝐴} ↔ 𝑦 <Q 𝐴) |
| 21 | 10, 6 | sotri 6147 |
. . . . . . . . 9
⊢ ((𝑧 <Q
𝑦 ∧ 𝑦 <Q 𝐴) → 𝑧 <Q 𝐴) |
| 22 | 21 | expcom 413 |
. . . . . . . 8
⊢ (𝑦 <Q
𝐴 → (𝑧 <Q
𝑦 → 𝑧 <Q 𝐴)) |
| 23 | 22 | adantl 481 |
. . . . . . 7
⊢ ((𝐴 ∈ Q ∧
𝑦
<Q 𝐴) → (𝑧 <Q 𝑦 → 𝑧 <Q 𝐴)) |
| 24 | | vex 3484 |
. . . . . . . 8
⊢ 𝑧 ∈ V |
| 25 | | breq1 5146 |
. . . . . . . 8
⊢ (𝑥 = 𝑧 → (𝑥 <Q 𝐴 ↔ 𝑧 <Q 𝐴)) |
| 26 | 24, 25 | elab 3679 |
. . . . . . 7
⊢ (𝑧 ∈ {𝑥 ∣ 𝑥 <Q 𝐴} ↔ 𝑧 <Q 𝐴) |
| 27 | 23, 26 | imbitrrdi 252 |
. . . . . 6
⊢ ((𝐴 ∈ Q ∧
𝑦
<Q 𝐴) → (𝑧 <Q 𝑦 → 𝑧 ∈ {𝑥 ∣ 𝑥 <Q 𝐴})) |
| 28 | 27 | alrimiv 1927 |
. . . . 5
⊢ ((𝐴 ∈ Q ∧
𝑦
<Q 𝐴) → ∀𝑧(𝑧 <Q 𝑦 → 𝑧 ∈ {𝑥 ∣ 𝑥 <Q 𝐴})) |
| 29 | | ltbtwnnq 11018 |
. . . . . . . 8
⊢ (𝑦 <Q
𝐴 ↔ ∃𝑧(𝑦 <Q 𝑧 ∧ 𝑧 <Q 𝐴)) |
| 30 | 26 | anbi2i 623 |
. . . . . . . . . . 11
⊢ ((𝑦 <Q
𝑧 ∧ 𝑧 ∈ {𝑥 ∣ 𝑥 <Q 𝐴}) ↔ (𝑦 <Q 𝑧 ∧ 𝑧 <Q 𝐴)) |
| 31 | 30 | biimpri 228 |
. . . . . . . . . 10
⊢ ((𝑦 <Q
𝑧 ∧ 𝑧 <Q 𝐴) → (𝑦 <Q 𝑧 ∧ 𝑧 ∈ {𝑥 ∣ 𝑥 <Q 𝐴})) |
| 32 | 31 | ancomd 461 |
. . . . . . . . 9
⊢ ((𝑦 <Q
𝑧 ∧ 𝑧 <Q 𝐴) → (𝑧 ∈ {𝑥 ∣ 𝑥 <Q 𝐴} ∧ 𝑦 <Q 𝑧)) |
| 33 | 32 | eximi 1835 |
. . . . . . . 8
⊢
(∃𝑧(𝑦 <Q
𝑧 ∧ 𝑧 <Q 𝐴) → ∃𝑧(𝑧 ∈ {𝑥 ∣ 𝑥 <Q 𝐴} ∧ 𝑦 <Q 𝑧)) |
| 34 | 29, 33 | sylbi 217 |
. . . . . . 7
⊢ (𝑦 <Q
𝐴 → ∃𝑧(𝑧 ∈ {𝑥 ∣ 𝑥 <Q 𝐴} ∧ 𝑦 <Q 𝑧)) |
| 35 | 34 | adantl 481 |
. . . . . 6
⊢ ((𝐴 ∈ Q ∧
𝑦
<Q 𝐴) → ∃𝑧(𝑧 ∈ {𝑥 ∣ 𝑥 <Q 𝐴} ∧ 𝑦 <Q 𝑧)) |
| 36 | | df-rex 3071 |
. . . . . 6
⊢
(∃𝑧 ∈
{𝑥 ∣ 𝑥 <Q
𝐴}𝑦 <Q 𝑧 ↔ ∃𝑧(𝑧 ∈ {𝑥 ∣ 𝑥 <Q 𝐴} ∧ 𝑦 <Q 𝑧)) |
| 37 | 35, 36 | sylibr 234 |
. . . . 5
⊢ ((𝐴 ∈ Q ∧
𝑦
<Q 𝐴) → ∃𝑧 ∈ {𝑥 ∣ 𝑥 <Q 𝐴}𝑦 <Q 𝑧) |
| 38 | 28, 37 | jca 511 |
. . . 4
⊢ ((𝐴 ∈ Q ∧
𝑦
<Q 𝐴) → (∀𝑧(𝑧 <Q 𝑦 → 𝑧 ∈ {𝑥 ∣ 𝑥 <Q 𝐴}) ∧ ∃𝑧 ∈ {𝑥 ∣ 𝑥 <Q 𝐴}𝑦 <Q 𝑧)) |
| 39 | 20, 38 | sylan2b 594 |
. . 3
⊢ ((𝐴 ∈ Q ∧
𝑦 ∈ {𝑥 ∣ 𝑥 <Q 𝐴}) → (∀𝑧(𝑧 <Q 𝑦 → 𝑧 ∈ {𝑥 ∣ 𝑥 <Q 𝐴}) ∧ ∃𝑧 ∈ {𝑥 ∣ 𝑥 <Q 𝐴}𝑦 <Q 𝑧)) |
| 40 | 39 | ralrimiva 3146 |
. 2
⊢ (𝐴 ∈ Q →
∀𝑦 ∈ {𝑥 ∣ 𝑥 <Q 𝐴} (∀𝑧(𝑧 <Q 𝑦 → 𝑧 ∈ {𝑥 ∣ 𝑥 <Q 𝐴}) ∧ ∃𝑧 ∈ {𝑥 ∣ 𝑥 <Q 𝐴}𝑦 <Q 𝑧)) |
| 41 | | elnp 11027 |
. 2
⊢ ({𝑥 ∣ 𝑥 <Q 𝐴} ∈ P ↔
((∅ ⊊ {𝑥
∣ 𝑥
<Q 𝐴} ∧ {𝑥 ∣ 𝑥 <Q 𝐴} ⊊ Q)
∧ ∀𝑦 ∈
{𝑥 ∣ 𝑥 <Q
𝐴} (∀𝑧(𝑧 <Q 𝑦 → 𝑧 ∈ {𝑥 ∣ 𝑥 <Q 𝐴}) ∧ ∃𝑧 ∈ {𝑥 ∣ 𝑥 <Q 𝐴}𝑦 <Q 𝑧))) |
| 42 | 5, 17, 40, 41 | syl21anbrc 1345 |
1
⊢ (𝐴 ∈ Q →
{𝑥 ∣ 𝑥 <Q
𝐴} ∈
P) |