Step | Hyp | Ref
| Expression |
1 | | fveq2 6896 |
. . 3
⊢ (𝑚 = 0s → ( bday ‘𝑚) = ( bday
‘ 0s )) |
2 | 1 | eleq1d 2810 |
. 2
⊢ (𝑚 = 0s → (( bday ‘𝑚) ∈ ω ↔ ( bday ‘ 0s ) ∈
ω)) |
3 | | fveq2 6896 |
. . 3
⊢ (𝑚 = 𝑛 → ( bday
‘𝑚) = ( bday ‘𝑛)) |
4 | 3 | eleq1d 2810 |
. 2
⊢ (𝑚 = 𝑛 → (( bday
‘𝑚) ∈
ω ↔ ( bday ‘𝑛) ∈ ω)) |
5 | | fveq2 6896 |
. . 3
⊢ (𝑚 = (𝑛 +s 1s ) → ( bday ‘𝑚) = ( bday
‘(𝑛
+s 1s ))) |
6 | 5 | eleq1d 2810 |
. 2
⊢ (𝑚 = (𝑛 +s 1s ) → (( bday ‘𝑚) ∈ ω ↔ ( bday ‘(𝑛 +s 1s )) ∈
ω)) |
7 | | fveq2 6896 |
. . 3
⊢ (𝑚 = 𝐴 → ( bday
‘𝑚) = ( bday ‘𝐴)) |
8 | 7 | eleq1d 2810 |
. 2
⊢ (𝑚 = 𝐴 → (( bday
‘𝑚) ∈
ω ↔ ( bday ‘𝐴) ∈ ω)) |
9 | | bday0s 27807 |
. . 3
⊢ ( bday ‘ 0s ) = ∅ |
10 | | peano1 7895 |
. . 3
⊢ ∅
∈ ω |
11 | 9, 10 | eqeltri 2821 |
. 2
⊢ ( bday ‘ 0s ) ∈
ω |
12 | | peano2n0s 28252 |
. . . . . . . . 9
⊢ (𝑛 ∈ ℕ0s
→ (𝑛 +s
1s ) ∈ ℕ0s) |
13 | | n0scut 28255 |
. . . . . . . . 9
⊢ ((𝑛 +s 1s )
∈ ℕ0s → (𝑛 +s 1s ) = ({((𝑛 +s 1s )
-s 1s )} |s ∅)) |
14 | 12, 13 | syl 17 |
. . . . . . . 8
⊢ (𝑛 ∈ ℕ0s
→ (𝑛 +s
1s ) = ({((𝑛
+s 1s ) -s 1s )} |s
∅)) |
15 | | n0sno 28245 |
. . . . . . . . . . 11
⊢ (𝑛 ∈ ℕ0s
→ 𝑛 ∈ No ) |
16 | | 1sno 27806 |
. . . . . . . . . . 11
⊢
1s ∈ No |
17 | | pncans 28028 |
. . . . . . . . . . 11
⊢ ((𝑛 ∈
No ∧ 1s ∈ No ) →
((𝑛 +s
1s ) -s 1s ) = 𝑛) |
18 | 15, 16, 17 | sylancl 584 |
. . . . . . . . . 10
⊢ (𝑛 ∈ ℕ0s
→ ((𝑛 +s
1s ) -s 1s ) = 𝑛) |
19 | 18 | sneqd 4642 |
. . . . . . . . 9
⊢ (𝑛 ∈ ℕ0s
→ {((𝑛 +s
1s ) -s 1s )} = {𝑛}) |
20 | 19 | oveq1d 7434 |
. . . . . . . 8
⊢ (𝑛 ∈ ℕ0s
→ ({((𝑛 +s
1s ) -s 1s )} |s ∅) = ({𝑛} |s ∅)) |
21 | 14, 20 | eqtrd 2765 |
. . . . . . 7
⊢ (𝑛 ∈ ℕ0s
→ (𝑛 +s
1s ) = ({𝑛} |s
∅)) |
22 | 21 | fveq2d 6900 |
. . . . . 6
⊢ (𝑛 ∈ ℕ0s
→ ( bday ‘(𝑛 +s 1s )) = ( bday ‘({𝑛} |s ∅))) |
23 | | snelpwi 5445 |
. . . . . . . 8
⊢ (𝑛 ∈
No → {𝑛}
∈ 𝒫 No ) |
24 | | nulssgt 27777 |
. . . . . . . 8
⊢ ({𝑛} ∈ 𝒫 No → {𝑛} <<s ∅) |
25 | 15, 23, 24 | 3syl 18 |
. . . . . . 7
⊢ (𝑛 ∈ ℕ0s
→ {𝑛} <<s
∅) |
26 | | un0 4392 |
. . . . . . . . . 10
⊢ ({𝑛} ∪ ∅) = {𝑛} |
27 | 26 | imaeq2i 6062 |
. . . . . . . . 9
⊢ ( bday “ ({𝑛} ∪ ∅)) = (
bday “ {𝑛}) |
28 | | bdayfn 27752 |
. . . . . . . . . 10
⊢ bday Fn No
|
29 | | fnsnfv 6976 |
. . . . . . . . . 10
⊢ (( bday Fn No ∧ 𝑛 ∈
No ) → {( bday ‘𝑛)} = (
bday “ {𝑛})) |
30 | 28, 15, 29 | sylancr 585 |
. . . . . . . . 9
⊢ (𝑛 ∈ ℕ0s
→ {( bday ‘𝑛)} = ( bday
“ {𝑛})) |
31 | 27, 30 | eqtr4id 2784 |
. . . . . . . 8
⊢ (𝑛 ∈ ℕ0s
→ ( bday “ ({𝑛} ∪ ∅)) = {(
bday ‘𝑛)}) |
32 | | fvex 6909 |
. . . . . . . . . 10
⊢ ( bday ‘𝑛) ∈ V |
33 | 32 | sucid 6453 |
. . . . . . . . 9
⊢ ( bday ‘𝑛) ∈ suc ( bday
‘𝑛) |
34 | | snssi 4813 |
. . . . . . . . 9
⊢ (( bday ‘𝑛) ∈ suc ( bday
‘𝑛) →
{( bday ‘𝑛)} ⊆ suc ( bday
‘𝑛)) |
35 | 33, 34 | ax-mp 5 |
. . . . . . . 8
⊢ {( bday ‘𝑛)} ⊆ suc ( bday
‘𝑛) |
36 | 31, 35 | eqsstrdi 4031 |
. . . . . . 7
⊢ (𝑛 ∈ ℕ0s
→ ( bday “ ({𝑛} ∪ ∅)) ⊆ suc ( bday ‘𝑛)) |
37 | | bdayelon 27755 |
. . . . . . . . 9
⊢ ( bday ‘𝑛) ∈ On |
38 | 37 | onsuci 7843 |
. . . . . . . 8
⊢ suc
( bday ‘𝑛) ∈ On |
39 | | scutbdaybnd 27794 |
. . . . . . . 8
⊢ (({𝑛} <<s ∅ ∧ suc
( bday ‘𝑛) ∈ On ∧ (
bday “ ({𝑛}
∪ ∅)) ⊆ suc ( bday ‘𝑛)) → ( bday ‘({𝑛} |s ∅)) ⊆ suc ( bday ‘𝑛)) |
40 | 38, 39 | mp3an2 1445 |
. . . . . . 7
⊢ (({𝑛} <<s ∅ ∧ ( bday “ ({𝑛} ∪ ∅)) ⊆ suc ( bday ‘𝑛)) → ( bday
‘({𝑛} |s
∅)) ⊆ suc ( bday ‘𝑛)) |
41 | 25, 36, 40 | syl2anc 582 |
. . . . . 6
⊢ (𝑛 ∈ ℕ0s
→ ( bday ‘({𝑛} |s ∅)) ⊆ suc ( bday ‘𝑛)) |
42 | 22, 41 | eqsstrd 4015 |
. . . . 5
⊢ (𝑛 ∈ ℕ0s
→ ( bday ‘(𝑛 +s 1s )) ⊆ suc
( bday ‘𝑛)) |
43 | | bdayelon 27755 |
. . . . . 6
⊢ ( bday ‘(𝑛 +s 1s )) ∈
On |
44 | | onsssuc 6461 |
. . . . . 6
⊢ ((( bday ‘(𝑛 +s 1s )) ∈ On
∧ suc ( bday ‘𝑛) ∈ On) → ((
bday ‘(𝑛
+s 1s )) ⊆ suc ( bday
‘𝑛) ↔
( bday ‘(𝑛 +s 1s )) ∈ suc
suc ( bday ‘𝑛))) |
45 | 43, 38, 44 | mp2an 690 |
. . . . 5
⊢ (( bday ‘(𝑛 +s 1s )) ⊆ suc
( bday ‘𝑛) ↔ ( bday
‘(𝑛
+s 1s )) ∈ suc suc ( bday
‘𝑛)) |
46 | 42, 45 | sylib 217 |
. . . 4
⊢ (𝑛 ∈ ℕ0s
→ ( bday ‘(𝑛 +s 1s )) ∈ suc
suc ( bday ‘𝑛)) |
47 | | peano2 7897 |
. . . . 5
⊢ (( bday ‘𝑛) ∈ ω → suc ( bday ‘𝑛) ∈ ω) |
48 | | peano2 7897 |
. . . . 5
⊢ (suc
( bday ‘𝑛) ∈ ω → suc suc ( bday ‘𝑛) ∈ ω) |
49 | 47, 48 | syl 17 |
. . . 4
⊢ (( bday ‘𝑛) ∈ ω → suc suc ( bday ‘𝑛) ∈ ω) |
50 | | elnn 7882 |
. . . 4
⊢ ((( bday ‘(𝑛 +s 1s )) ∈ suc
suc ( bday ‘𝑛) ∧ suc suc ( bday
‘𝑛) ∈
ω) → ( bday ‘(𝑛 +s 1s )) ∈
ω) |
51 | 46, 49, 50 | syl2an 594 |
. . 3
⊢ ((𝑛 ∈ ℕ0s
∧ ( bday ‘𝑛) ∈ ω) → ( bday ‘(𝑛 +s 1s )) ∈
ω) |
52 | 51 | ex 411 |
. 2
⊢ (𝑛 ∈ ℕ0s
→ (( bday ‘𝑛) ∈ ω → ( bday ‘(𝑛 +s 1s )) ∈
ω)) |
53 | 2, 4, 6, 8, 11, 52 | n0sind 28254 |
1
⊢ (𝐴 ∈ ℕ0s
→ ( bday ‘𝐴) ∈ ω) |