Metamath Proof Explorer


Definition df-bj-inftyexpitau

Description: Definition of the auxiliary function inftyexpitau parameterizing the circle at infinity CCinfty in CCbar . We use coupling with { R. } to simplify the proof of bj-inftyexpitaudisj . (Contributed by BJ, 22-Jan-2023) The precise definition is irrelevant and should generally not be used. TODO: prove only the necessary lemmas to prove |- ( A e. RR /\ B e. RR ) -> ( ( inftyexpitauA ) = ( inftyexpitauB ) <-> ( A - B ) e. ZZ ) ) . (New usage is discouraged.)

Ref Expression
Assertion df-bj-inftyexpitau +āˆžeiĻ„ = ( š‘„ āˆˆ ā„ ā†¦ āŸØ ( {R ā€˜ ( 1st ā€˜ š‘„ ) ) , { R } āŸ© )

Detailed syntax breakdown

Step Hyp Ref Expression
0 cinftyexpitau āŠ¢ +āˆžeiĻ„
1 vx āŠ¢ š‘„
2 cr āŠ¢ ā„
3 cfractemp āŠ¢ {R
4 c1st āŠ¢ 1st
5 1 cv āŠ¢ š‘„
6 5 4 cfv āŠ¢ ( 1st ā€˜ š‘„ )
7 6 3 cfv āŠ¢ ( {R ā€˜ ( 1st ā€˜ š‘„ ) )
8 cnr āŠ¢ R
9 8 csn āŠ¢ { R }
10 7 9 cop āŠ¢ āŸØ ( {R ā€˜ ( 1st ā€˜ š‘„ ) ) , { R } āŸ©
11 1 2 10 cmpt āŠ¢ ( š‘„ āˆˆ ā„ ā†¦ āŸØ ( {R ā€˜ ( 1st ā€˜ š‘„ ) ) , { R } āŸ© )
12 0 11 wceq āŠ¢ +āˆžeiĻ„ = ( š‘„ āˆˆ ā„ ā†¦ āŸØ ( {R ā€˜ ( 1st ā€˜ š‘„ ) ) , { R } āŸ© )