Step | Hyp | Ref
| Expression |
1 | | itcoval 47300 |
. . . 4
β’ (πΉ β π β (IterCompβπΉ) = seq0((π β V, π β V β¦ (πΉ β π)), (π β β0 β¦ if(π = 0, ( I βΎ dom πΉ), πΉ)))) |
2 | 1 | fveq1d 6890 |
. . 3
β’ (πΉ β π β ((IterCompβπΉ)β2) = (seq0((π β V, π β V β¦ (πΉ β π)), (π β β0 β¦ if(π = 0, ( I βΎ dom πΉ), πΉ)))β2)) |
3 | 2 | adantl 482 |
. 2
β’ ((Rel
πΉ β§ πΉ β π) β ((IterCompβπΉ)β2) = (seq0((π β V, π β V β¦ (πΉ β π)), (π β β0 β¦ if(π = 0, ( I βΎ dom πΉ), πΉ)))β2)) |
4 | | nn0uz 12860 |
. . 3
β’
β0 = (β€β₯β0) |
5 | | 1nn0 12484 |
. . . 4
β’ 1 β
β0 |
6 | 5 | a1i 11 |
. . 3
β’ ((Rel
πΉ β§ πΉ β π) β 1 β
β0) |
7 | | df-2 12271 |
. . 3
β’ 2 = (1 +
1) |
8 | 1 | eqcomd 2738 |
. . . . . 6
β’ (πΉ β π β seq0((π β V, π β V β¦ (πΉ β π)), (π β β0 β¦ if(π = 0, ( I βΎ dom πΉ), πΉ))) = (IterCompβπΉ)) |
9 | 8 | fveq1d 6890 |
. . . . 5
β’ (πΉ β π β (seq0((π β V, π β V β¦ (πΉ β π)), (π β β0 β¦ if(π = 0, ( I βΎ dom πΉ), πΉ)))β1) = ((IterCompβπΉ)β1)) |
10 | 9 | adantl 482 |
. . . 4
β’ ((Rel
πΉ β§ πΉ β π) β (seq0((π β V, π β V β¦ (πΉ β π)), (π β β0 β¦ if(π = 0, ( I βΎ dom πΉ), πΉ)))β1) = ((IterCompβπΉ)β1)) |
11 | | itcoval1 47302 |
. . . 4
β’ ((Rel
πΉ β§ πΉ β π) β ((IterCompβπΉ)β1) = πΉ) |
12 | 10, 11 | eqtrd 2772 |
. . 3
β’ ((Rel
πΉ β§ πΉ β π) β (seq0((π β V, π β V β¦ (πΉ β π)), (π β β0 β¦ if(π = 0, ( I βΎ dom πΉ), πΉ)))β1) = πΉ) |
13 | | eqidd 2733 |
. . . 4
β’ ((Rel
πΉ β§ πΉ β π) β (π β β0 β¦ if(π = 0, ( I βΎ dom πΉ), πΉ)) = (π β β0 β¦ if(π = 0, ( I βΎ dom πΉ), πΉ))) |
14 | | 2ne0 12312 |
. . . . . . . 8
β’ 2 β
0 |
15 | | neeq1 3003 |
. . . . . . . 8
β’ (π = 2 β (π β 0 β 2 β 0)) |
16 | 14, 15 | mpbiri 257 |
. . . . . . 7
β’ (π = 2 β π β 0) |
17 | 16 | neneqd 2945 |
. . . . . 6
β’ (π = 2 β Β¬ π = 0) |
18 | 17 | iffalsed 4538 |
. . . . 5
β’ (π = 2 β if(π = 0, ( I βΎ dom πΉ), πΉ) = πΉ) |
19 | 18 | adantl 482 |
. . . 4
β’ (((Rel
πΉ β§ πΉ β π) β§ π = 2) β if(π = 0, ( I βΎ dom πΉ), πΉ) = πΉ) |
20 | | 2nn0 12485 |
. . . . 5
β’ 2 β
β0 |
21 | 20 | a1i 11 |
. . . 4
β’ ((Rel
πΉ β§ πΉ β π) β 2 β
β0) |
22 | | simpr 485 |
. . . 4
β’ ((Rel
πΉ β§ πΉ β π) β πΉ β π) |
23 | 13, 19, 21, 22 | fvmptd 7002 |
. . 3
β’ ((Rel
πΉ β§ πΉ β π) β ((π β β0 β¦ if(π = 0, ( I βΎ dom πΉ), πΉ))β2) = πΉ) |
24 | 4, 6, 7, 12, 23 | seqp1d 13979 |
. 2
β’ ((Rel
πΉ β§ πΉ β π) β (seq0((π β V, π β V β¦ (πΉ β π)), (π β β0 β¦ if(π = 0, ( I βΎ dom πΉ), πΉ)))β2) = (πΉ(π β V, π β V β¦ (πΉ β π))πΉ)) |
25 | | eqidd 2733 |
. . . 4
β’ (πΉ β π β (π β V, π β V β¦ (πΉ β π)) = (π β V, π β V β¦ (πΉ β π))) |
26 | | coeq2 5856 |
. . . . 5
β’ (π = πΉ β (πΉ β π) = (πΉ β πΉ)) |
27 | 26 | ad2antrl 726 |
. . . 4
β’ ((πΉ β π β§ (π = πΉ β§ π = πΉ)) β (πΉ β π) = (πΉ β πΉ)) |
28 | | elex 3492 |
. . . 4
β’ (πΉ β π β πΉ β V) |
29 | | coexg 7916 |
. . . . 5
β’ ((πΉ β π β§ πΉ β π) β (πΉ β πΉ) β V) |
30 | 29 | anidms 567 |
. . . 4
β’ (πΉ β π β (πΉ β πΉ) β V) |
31 | 25, 27, 28, 28, 30 | ovmpod 7556 |
. . 3
β’ (πΉ β π β (πΉ(π β V, π β V β¦ (πΉ β π))πΉ) = (πΉ β πΉ)) |
32 | 31 | adantl 482 |
. 2
β’ ((Rel
πΉ β§ πΉ β π) β (πΉ(π β V, π β V β¦ (πΉ β π))πΉ) = (πΉ β πΉ)) |
33 | 3, 24, 32 | 3eqtrd 2776 |
1
β’ ((Rel
πΉ β§ πΉ β π) β ((IterCompβπΉ)β2) = (πΉ β πΉ)) |