Metamath Proof Explorer


Theorem bj-iomnnom

Description: The canonical bijection from (om u. { om } ) onto ( NN0 u. { pinfty } ) maps _om to pinfty . (Contributed by BJ, 18-Feb-2023)

Ref Expression
Assertion bj-iomnnom
|- ( iomnn ` _om ) = pinfty

Proof

Step Hyp Ref Expression
1 df-bj-iomnn
 |-  iomnn = ( ( n e. _om |-> <. [ <. { r e. Q. | r . } , 1P >. ] ~R , 0R >. ) u. { <. _om , pinfty >. } )
2 1 a1i
 |-  ( T. -> iomnn = ( ( n e. _om |-> <. [ <. { r e. Q. | r . } , 1P >. ] ~R , 0R >. ) u. { <. _om , pinfty >. } ) )
3 ordom
 |-  Ord _om
4 ordirr
 |-  ( Ord _om -> -. _om e. _om )
5 3 4 ax-mp
 |-  -. _om e. _om
6 5 a1i
 |-  ( T. -> -. _om e. _om )
7 omex
 |-  _om e. _V
8 7 a1i
 |-  ( T. -> _om e. _V )
9 bj-pinftyccb
 |-  pinfty e. CCbar
10 9 a1i
 |-  ( T. -> pinfty e. CCbar )
11 2 6 8 10 bj-fvmptunsn1
 |-  ( T. -> ( iomnn ` _om ) = pinfty )
12 11 mptru
 |-  ( iomnn ` _om ) = pinfty