Metamath Proof Explorer


Theorem symgmov2

Description: For a permutation of a set, each element of the set is replaced by an(other) element of the set. (Contributed by AV, 2-Jan-2019)

Ref Expression
Hypothesis symgmov1.p
|- P = ( Base ` ( SymGrp ` N ) )
Assertion symgmov2
|- ( Q e. P -> A. n e. N E. k e. N ( Q ` k ) = n )

Proof

Step Hyp Ref Expression
1 symgmov1.p
 |-  P = ( Base ` ( SymGrp ` N ) )
2 eqid
 |-  ( SymGrp ` N ) = ( SymGrp ` N )
3 2 1 symgbasf1o
 |-  ( Q e. P -> Q : N -1-1-onto-> N )
4 f1ofo
 |-  ( Q : N -1-1-onto-> N -> Q : N -onto-> N )
5 foelrni
 |-  ( ( Q : N -onto-> N /\ n e. N ) -> E. k e. N ( Q ` k ) = n )
6 5 ralrimiva
 |-  ( Q : N -onto-> N -> A. n e. N E. k e. N ( Q ` k ) = n )
7 3 4 6 3syl
 |-  ( Q e. P -> A. n e. N E. k e. N ( Q ` k ) = n )