Step | Hyp | Ref
| Expression |
1 | | df-suc 6368 |
. . . . . . . 8
β’ suc π΄ = (π΄ βͺ {π΄}) |
2 | 1 | imaeq2i 6056 |
. . . . . . 7
β’ ( M
β suc π΄) = ( M
β (π΄ βͺ {π΄})) |
3 | | imaundi 6147 |
. . . . . . 7
β’ ( M
β (π΄ βͺ {π΄})) = (( M β π΄) βͺ ( M β {π΄})) |
4 | 2, 3 | eqtri 2761 |
. . . . . 6
β’ ( M
β suc π΄) = (( M
β π΄) βͺ ( M
β {π΄})) |
5 | 4 | unieqi 4921 |
. . . . 5
β’ βͺ ( M β suc π΄) = βͺ (( M
β π΄) βͺ ( M
β {π΄})) |
6 | | uniun 4934 |
. . . . 5
β’ βͺ (( M β π΄) βͺ ( M β {π΄})) = (βͺ ( M
β π΄) βͺ βͺ ( M β {π΄})) |
7 | 5, 6 | eqtri 2761 |
. . . 4
β’ βͺ ( M β suc π΄) = (βͺ ( M
β π΄) βͺ βͺ ( M β {π΄})) |
8 | 7 | a1i 11 |
. . 3
β’ (π΄ β On β βͺ ( M β suc π΄) = (βͺ ( M
β π΄) βͺ βͺ ( M β {π΄}))) |
9 | | oldval 27339 |
. . . . 5
β’ (π΄ β On β ( O
βπ΄) = βͺ ( M β π΄)) |
10 | 9 | eqcomd 2739 |
. . . 4
β’ (π΄ β On β βͺ ( M β π΄) = ( O βπ΄)) |
11 | | madef 27341 |
. . . . . . . 8
β’ M
:OnβΆπ« No |
12 | | ffn 6715 |
. . . . . . . 8
β’ ( M
:OnβΆπ« No β M Fn
On) |
13 | 11, 12 | ax-mp 5 |
. . . . . . 7
β’ M Fn
On |
14 | | fnsnfv 6968 |
. . . . . . . 8
β’ (( M Fn
On β§ π΄ β On)
β {( M βπ΄)} = (
M β {π΄})) |
15 | 14 | eqcomd 2739 |
. . . . . . 7
β’ (( M Fn
On β§ π΄ β On)
β ( M β {π΄}) =
{( M βπ΄)}) |
16 | 13, 15 | mpan 689 |
. . . . . 6
β’ (π΄ β On β ( M β
{π΄}) = {( M βπ΄)}) |
17 | 16 | unieqd 4922 |
. . . . 5
β’ (π΄ β On β βͺ ( M β {π΄}) = βͺ {( M
βπ΄)}) |
18 | | fvex 6902 |
. . . . . 6
β’ ( M
βπ΄) β
V |
19 | 18 | unisn 4930 |
. . . . 5
β’ βͺ {( M βπ΄)} = ( M βπ΄) |
20 | 17, 19 | eqtrdi 2789 |
. . . 4
β’ (π΄ β On β βͺ ( M β {π΄}) = ( M βπ΄)) |
21 | 10, 20 | uneq12d 4164 |
. . 3
β’ (π΄ β On β (βͺ ( M β π΄) βͺ βͺ ( M
β {π΄})) = (( O
βπ΄) βͺ ( M
βπ΄))) |
22 | | oldssmade 27362 |
. . . . 5
β’ ( O
βπ΄) β ( M
βπ΄) |
23 | 22 | a1i 11 |
. . . 4
β’ (π΄ β On β ( O
βπ΄) β ( M
βπ΄)) |
24 | | ssequn1 4180 |
. . . 4
β’ (( O
βπ΄) β ( M
βπ΄) β (( O
βπ΄) βͺ ( M
βπ΄)) = ( M
βπ΄)) |
25 | 23, 24 | sylib 217 |
. . 3
β’ (π΄ β On β (( O
βπ΄) βͺ ( M
βπ΄)) = ( M
βπ΄)) |
26 | 8, 21, 25 | 3eqtrrd 2778 |
. 2
β’ (π΄ β On β ( M
βπ΄) = βͺ ( M β suc π΄)) |
27 | | onsuc 7796 |
. . 3
β’ (π΄ β On β suc π΄ β On) |
28 | | oldval 27339 |
. . 3
β’ (suc
π΄ β On β ( O
βsuc π΄) = βͺ ( M β suc π΄)) |
29 | 27, 28 | syl 17 |
. 2
β’ (π΄ β On β ( O βsuc
π΄) = βͺ ( M β suc π΄)) |
30 | 26, 29 | eqtr4d 2776 |
1
β’ (π΄ β On β ( M
βπ΄) = ( O βsuc
π΄)) |