Metamath Proof Explorer


Theorem jk1k2k3

Description: Identity law for the _J function. Proposition 15.8 of TakeutiZaring p. 156. (Contributed by BTernaryTau, 11-Oct-2026)

Ref Expression
Assertion jk1k2k3 Could not format assertion : No typesetting found for |- ( A e. On -> A = ( _J ` <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) ) with typecode |-

Proof

Step Hyp Ref Expression
1 jf1o Could not format _J : ( ( On X. On ) X. 9o ) -1-1-onto-> On : No typesetting found for |- _J : ( ( On X. On ) X. 9o ) -1-1-onto-> On with typecode |-
2 f1ocnvdm Could not format ( ( _J : ( ( On X. On ) X. 9o ) -1-1-onto-> On /\ A e. On ) -> ( `' _J ` A ) e. ( ( On X. On ) X. 9o ) ) : No typesetting found for |- ( ( _J : ( ( On X. On ) X. 9o ) -1-1-onto-> On /\ A e. On ) -> ( `' _J ` A ) e. ( ( On X. On ) X. 9o ) ) with typecode |-
3 1 2 mpan Could not format ( A e. On -> ( `' _J ` A ) e. ( ( On X. On ) X. 9o ) ) : No typesetting found for |- ( A e. On -> ( `' _J ` A ) e. ( ( On X. On ) X. 9o ) ) with typecode |-
4 2fveq3 Could not format ( x = A -> ( 1st ` ( `' _J ` x ) ) = ( 1st ` ( `' _J ` A ) ) ) : No typesetting found for |- ( x = A -> ( 1st ` ( `' _J ` x ) ) = ( 1st ` ( `' _J ` A ) ) ) with typecode |-
5 4 fveq2d Could not format ( x = A -> ( 1st ` ( 1st ` ( `' _J ` x ) ) ) = ( 1st ` ( 1st ` ( `' _J ` A ) ) ) ) : No typesetting found for |- ( x = A -> ( 1st ` ( 1st ` ( `' _J ` x ) ) ) = ( 1st ` ( 1st ` ( `' _J ` A ) ) ) ) with typecode |-
6 dfk12 Could not format _K1 = ( x e. On |-> ( 1st ` ( 1st ` ( `' _J ` x ) ) ) ) : No typesetting found for |- _K1 = ( x e. On |-> ( 1st ` ( 1st ` ( `' _J ` x ) ) ) ) with typecode |-
7 fvex Could not format ( 1st ` ( 1st ` ( `' _J ` A ) ) ) e. _V : No typesetting found for |- ( 1st ` ( 1st ` ( `' _J ` A ) ) ) e. _V with typecode |-
8 5 6 7 fvmpt Could not format ( A e. On -> ( _K1 ` A ) = ( 1st ` ( 1st ` ( `' _J ` A ) ) ) ) : No typesetting found for |- ( A e. On -> ( _K1 ` A ) = ( 1st ` ( 1st ` ( `' _J ` A ) ) ) ) with typecode |-
9 8 eqcomd Could not format ( A e. On -> ( 1st ` ( 1st ` ( `' _J ` A ) ) ) = ( _K1 ` A ) ) : No typesetting found for |- ( A e. On -> ( 1st ` ( 1st ` ( `' _J ` A ) ) ) = ( _K1 ` A ) ) with typecode |-
10 4 fveq2d Could not format ( x = A -> ( 2nd ` ( 1st ` ( `' _J ` x ) ) ) = ( 2nd ` ( 1st ` ( `' _J ` A ) ) ) ) : No typesetting found for |- ( x = A -> ( 2nd ` ( 1st ` ( `' _J ` x ) ) ) = ( 2nd ` ( 1st ` ( `' _J ` A ) ) ) ) with typecode |-
11 dfk22 Could not format _K2 = ( x e. On |-> ( 2nd ` ( 1st ` ( `' _J ` x ) ) ) ) : No typesetting found for |- _K2 = ( x e. On |-> ( 2nd ` ( 1st ` ( `' _J ` x ) ) ) ) with typecode |-
12 fvex Could not format ( 2nd ` ( 1st ` ( `' _J ` A ) ) ) e. _V : No typesetting found for |- ( 2nd ` ( 1st ` ( `' _J ` A ) ) ) e. _V with typecode |-
13 10 11 12 fvmpt Could not format ( A e. On -> ( _K2 ` A ) = ( 2nd ` ( 1st ` ( `' _J ` A ) ) ) ) : No typesetting found for |- ( A e. On -> ( _K2 ` A ) = ( 2nd ` ( 1st ` ( `' _J ` A ) ) ) ) with typecode |-
14 13 eqcomd Could not format ( A e. On -> ( 2nd ` ( 1st ` ( `' _J ` A ) ) ) = ( _K2 ` A ) ) : No typesetting found for |- ( A e. On -> ( 2nd ` ( 1st ` ( `' _J ` A ) ) ) = ( _K2 ` A ) ) with typecode |-
15 2fveq3 Could not format ( x = A -> ( 2nd ` ( `' _J ` x ) ) = ( 2nd ` ( `' _J ` A ) ) ) : No typesetting found for |- ( x = A -> ( 2nd ` ( `' _J ` x ) ) = ( 2nd ` ( `' _J ` A ) ) ) with typecode |-
16 dfk32 Could not format _K3 = ( x e. On |-> ( 2nd ` ( `' _J ` x ) ) ) : No typesetting found for |- _K3 = ( x e. On |-> ( 2nd ` ( `' _J ` x ) ) ) with typecode |-
17 fvex Could not format ( 2nd ` ( `' _J ` A ) ) e. _V : No typesetting found for |- ( 2nd ` ( `' _J ` A ) ) e. _V with typecode |-
18 15 16 17 fvmpt Could not format ( A e. On -> ( _K3 ` A ) = ( 2nd ` ( `' _J ` A ) ) ) : No typesetting found for |- ( A e. On -> ( _K3 ` A ) = ( 2nd ` ( `' _J ` A ) ) ) with typecode |-
19 18 eqcomd Could not format ( A e. On -> ( 2nd ` ( `' _J ` A ) ) = ( _K3 ` A ) ) : No typesetting found for |- ( A e. On -> ( 2nd ` ( `' _J ` A ) ) = ( _K3 ` A ) ) with typecode |-
20 9 14 19 3jca Could not format ( A e. On -> ( ( 1st ` ( 1st ` ( `' _J ` A ) ) ) = ( _K1 ` A ) /\ ( 2nd ` ( 1st ` ( `' _J ` A ) ) ) = ( _K2 ` A ) /\ ( 2nd ` ( `' _J ` A ) ) = ( _K3 ` A ) ) ) : No typesetting found for |- ( A e. On -> ( ( 1st ` ( 1st ` ( `' _J ` A ) ) ) = ( _K1 ` A ) /\ ( 2nd ` ( 1st ` ( `' _J ` A ) ) ) = ( _K2 ` A ) /\ ( 2nd ` ( `' _J ` A ) ) = ( _K3 ` A ) ) ) with typecode |-
21 3 20 jca Could not format ( A e. On -> ( ( `' _J ` A ) e. ( ( On X. On ) X. 9o ) /\ ( ( 1st ` ( 1st ` ( `' _J ` A ) ) ) = ( _K1 ` A ) /\ ( 2nd ` ( 1st ` ( `' _J ` A ) ) ) = ( _K2 ` A ) /\ ( 2nd ` ( `' _J ` A ) ) = ( _K3 ` A ) ) ) ) : No typesetting found for |- ( A e. On -> ( ( `' _J ` A ) e. ( ( On X. On ) X. 9o ) /\ ( ( 1st ` ( 1st ` ( `' _J ` A ) ) ) = ( _K1 ` A ) /\ ( 2nd ` ( 1st ` ( `' _J ` A ) ) ) = ( _K2 ` A ) /\ ( 2nd ` ( `' _J ` A ) ) = ( _K3 ` A ) ) ) ) with typecode |-
22 k1on Could not format ( _K1 ` A ) e. On : No typesetting found for |- ( _K1 ` A ) e. On with typecode |-
23 k2on Could not format ( _K2 ` A ) e. On : No typesetting found for |- ( _K2 ` A ) e. On with typecode |-
24 k39o Could not format ( _K3 ` A ) e. 9o : No typesetting found for |- ( _K3 ` A ) e. 9o with typecode |-
25 el2xptp0 Could not format ( ( ( _K1 ` A ) e. On /\ ( _K2 ` A ) e. On /\ ( _K3 ` A ) e. 9o ) -> ( ( ( `' _J ` A ) e. ( ( On X. On ) X. 9o ) /\ ( ( 1st ` ( 1st ` ( `' _J ` A ) ) ) = ( _K1 ` A ) /\ ( 2nd ` ( 1st ` ( `' _J ` A ) ) ) = ( _K2 ` A ) /\ ( 2nd ` ( `' _J ` A ) ) = ( _K3 ` A ) ) ) <-> ( `' _J ` A ) = <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) ) : No typesetting found for |- ( ( ( _K1 ` A ) e. On /\ ( _K2 ` A ) e. On /\ ( _K3 ` A ) e. 9o ) -> ( ( ( `' _J ` A ) e. ( ( On X. On ) X. 9o ) /\ ( ( 1st ` ( 1st ` ( `' _J ` A ) ) ) = ( _K1 ` A ) /\ ( 2nd ` ( 1st ` ( `' _J ` A ) ) ) = ( _K2 ` A ) /\ ( 2nd ` ( `' _J ` A ) ) = ( _K3 ` A ) ) ) <-> ( `' _J ` A ) = <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) ) with typecode |-
26 22 23 24 25 mp3an Could not format ( ( ( `' _J ` A ) e. ( ( On X. On ) X. 9o ) /\ ( ( 1st ` ( 1st ` ( `' _J ` A ) ) ) = ( _K1 ` A ) /\ ( 2nd ` ( 1st ` ( `' _J ` A ) ) ) = ( _K2 ` A ) /\ ( 2nd ` ( `' _J ` A ) ) = ( _K3 ` A ) ) ) <-> ( `' _J ` A ) = <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) : No typesetting found for |- ( ( ( `' _J ` A ) e. ( ( On X. On ) X. 9o ) /\ ( ( 1st ` ( 1st ` ( `' _J ` A ) ) ) = ( _K1 ` A ) /\ ( 2nd ` ( 1st ` ( `' _J ` A ) ) ) = ( _K2 ` A ) /\ ( 2nd ` ( `' _J ` A ) ) = ( _K3 ` A ) ) ) <-> ( `' _J ` A ) = <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) with typecode |-
27 21 26 sylib Could not format ( A e. On -> ( `' _J ` A ) = <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) : No typesetting found for |- ( A e. On -> ( `' _J ` A ) = <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) with typecode |-
28 27 3 eqeltrrd Could not format ( A e. On -> <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. e. ( ( On X. On ) X. 9o ) ) : No typesetting found for |- ( A e. On -> <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. e. ( ( On X. On ) X. 9o ) ) with typecode |-
29 f1ocnvfvb Could not format ( ( _J : ( ( On X. On ) X. 9o ) -1-1-onto-> On /\ <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. e. ( ( On X. On ) X. 9o ) /\ A e. On ) -> ( ( _J ` <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) = A <-> ( `' _J ` A ) = <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) ) : No typesetting found for |- ( ( _J : ( ( On X. On ) X. 9o ) -1-1-onto-> On /\ <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. e. ( ( On X. On ) X. 9o ) /\ A e. On ) -> ( ( _J ` <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) = A <-> ( `' _J ` A ) = <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) ) with typecode |-
30 1 29 mp3an1 Could not format ( ( <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. e. ( ( On X. On ) X. 9o ) /\ A e. On ) -> ( ( _J ` <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) = A <-> ( `' _J ` A ) = <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) ) : No typesetting found for |- ( ( <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. e. ( ( On X. On ) X. 9o ) /\ A e. On ) -> ( ( _J ` <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) = A <-> ( `' _J ` A ) = <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) ) with typecode |-
31 28 30 mpancom Could not format ( A e. On -> ( ( _J ` <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) = A <-> ( `' _J ` A ) = <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) ) : No typesetting found for |- ( A e. On -> ( ( _J ` <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) = A <-> ( `' _J ` A ) = <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) ) with typecode |-
32 27 31 mpbird Could not format ( A e. On -> ( _J ` <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) = A ) : No typesetting found for |- ( A e. On -> ( _J ` <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) = A ) with typecode |-
33 32 eqcomd Could not format ( A e. On -> A = ( _J ` <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) ) : No typesetting found for |- ( A e. On -> A = ( _J ` <. ( _K1 ` A ) , ( _K2 ` A ) , ( _K3 ` A ) >. ) ) with typecode |-