Step | Hyp | Ref
| Expression |
1 | | simp1 1136 |
. . 3
β’ ((πΉ β π β§ π β β0 β§
((IterCompβπΉ)βπ) = πΊ) β πΉ β π) |
2 | | itcoval 46900 |
. . . 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)))) |
3 | 2 | fveq1d 6864 |
. . 3
β’ (πΉ β π β ((IterCompβπΉ)β(π + 1)) = (seq0((π β V, π β V β¦ (πΉ β π)), (π β β0 β¦ if(π = 0, ( I βΎ dom πΉ), πΉ)))β(π + 1))) |
4 | 1, 3 | syl 17 |
. 2
β’ ((πΉ β π β§ π β β0 β§
((IterCompβπΉ)βπ) = πΊ) β ((IterCompβπΉ)β(π + 1)) = (seq0((π β V, π β V β¦ (πΉ β π)), (π β β0 β¦ if(π = 0, ( I βΎ dom πΉ), πΉ)))β(π + 1))) |
5 | | nn0uz 12829 |
. . 3
β’
β0 = (β€β₯β0) |
6 | | simp2 1137 |
. . 3
β’ ((πΉ β π β§ π β β0 β§
((IterCompβπΉ)βπ) = πΊ) β π β
β0) |
7 | | eqid 2731 |
. . 3
β’ (π + 1) = (π + 1) |
8 | 2 | adantr 481 |
. . . . . 6
β’ ((πΉ β π β§ π β β0) 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)))) |
9 | 8 | fveq1d 6864 |
. . . . 5
β’ ((πΉ β π β§ π β β0) β
((IterCompβπΉ)βπ) = (seq0((π β V, π β V β¦ (πΉ β π)), (π β β0 β¦ if(π = 0, ( I βΎ dom πΉ), πΉ)))βπ)) |
10 | 9 | eqeq1d 2733 |
. . . 4
β’ ((πΉ β π β§ π β β0) β
(((IterCompβπΉ)βπ) = πΊ β (seq0((π β V, π β V β¦ (πΉ β π)), (π β β0 β¦ if(π = 0, ( I βΎ dom πΉ), πΉ)))βπ) = πΊ)) |
11 | 10 | biimp3a 1469 |
. . 3
β’ ((πΉ β π β§ π β β0 β§
((IterCompβπΉ)βπ) = πΊ) β (seq0((π β V, π β V β¦ (πΉ β π)), (π β β0 β¦ if(π = 0, ( I βΎ dom πΉ), πΉ)))βπ) = πΊ) |
12 | | eqidd 2732 |
. . . 4
β’ ((πΉ β π β§ π β β0 β§
((IterCompβπΉ)βπ) = πΊ) 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))) |
13 | | nn0p1gt0 12466 |
. . . . . . . . . 10
β’ (π β β0
β 0 < (π +
1)) |
14 | 13 | 3ad2ant2 1134 |
. . . . . . . . 9
β’ ((πΉ β π β§ π β β0 β§
((IterCompβπΉ)βπ) = πΊ) β 0 < (π + 1)) |
15 | 14 | gt0ne0d 11743 |
. . . . . . . 8
β’ ((πΉ β π β§ π β β0 β§
((IterCompβπΉ)βπ) = πΊ) β (π + 1) β 0) |
16 | 15 | adantr 481 |
. . . . . . 7
β’ (((πΉ β π β§ π β β0 β§
((IterCompβπΉ)βπ) = πΊ) β§ π = (π + 1)) β (π + 1) β 0) |
17 | | neeq1 3002 |
. . . . . . . 8
β’ (π = (π + 1) β (π β 0 β (π + 1) β 0)) |
18 | 17 | adantl 482 |
. . . . . . 7
β’ (((πΉ β π β§ π β β0 β§
((IterCompβπΉ)βπ) = πΊ) β§ π = (π + 1)) β (π β 0 β (π + 1) β 0)) |
19 | 16, 18 | mpbird 256 |
. . . . . 6
β’ (((πΉ β π β§ π β β0 β§
((IterCompβπΉ)βπ) = πΊ) β§ π = (π + 1)) β π β 0) |
20 | 19 | neneqd 2944 |
. . . . 5
β’ (((πΉ β π β§ π β β0 β§
((IterCompβπΉ)βπ) = πΊ) β§ π = (π + 1)) β Β¬ π = 0) |
21 | 20 | iffalsed 4517 |
. . . 4
β’ (((πΉ β π β§ π β β0 β§
((IterCompβπΉ)βπ) = πΊ) β§ π = (π + 1)) β if(π = 0, ( I βΎ dom πΉ), πΉ) = πΉ) |
22 | | peano2nn0 12477 |
. . . . 5
β’ (π β β0
β (π + 1) β
β0) |
23 | 22 | 3ad2ant2 1134 |
. . . 4
β’ ((πΉ β π β§ π β β0 β§
((IterCompβπΉ)βπ) = πΊ) β (π + 1) β
β0) |
24 | 12, 21, 23, 1 | fvmptd 6975 |
. . 3
β’ ((πΉ β π β§ π β β0 β§
((IterCompβπΉ)βπ) = πΊ) β ((π β β0 β¦ if(π = 0, ( I βΎ dom πΉ), πΉ))β(π + 1)) = πΉ) |
25 | 5, 6, 7, 11, 24 | seqp1d 13948 |
. 2
β’ ((πΉ β π β§ π β β0 β§
((IterCompβπΉ)βπ) = πΊ) β (seq0((π β V, π β V β¦ (πΉ β π)), (π β β0 β¦ if(π = 0, ( I βΎ dom πΉ), πΉ)))β(π + 1)) = (πΊ(π β V, π β V β¦ (πΉ β π))πΉ)) |
26 | 4, 25 | eqtrd 2771 |
1
β’ ((πΉ β π β§ π β β0 β§
((IterCompβπΉ)βπ) = πΊ) β ((IterCompβπΉ)β(π + 1)) = (πΊ(π β V, π β V β¦ (πΉ β π))πΉ)) |