Metamath Proof Explorer


Theorem nodenselem6

Description: The restriction of a surreal to the abstraction from nodenselem4 is still a surreal. (Contributed by Scott Fenton, 16-Jun-2011)

Ref Expression
Assertion nodenselem6
|- ( ( ( A e. No /\ B e. No ) /\ ( ( bday ` A ) = ( bday ` B ) /\ A  ( A |` |^| { a e. On | ( A ` a ) =/= ( B ` a ) } ) e. No )

Proof

Step Hyp Ref Expression
1 simpll
 |-  ( ( ( A e. No /\ B e. No ) /\ ( ( bday ` A ) = ( bday ` B ) /\ A  A e. No )
2 nodenselem4
 |-  ( ( ( A e. No /\ B e. No ) /\ A  |^| { a e. On | ( A ` a ) =/= ( B ` a ) } e. On )
3 2 adantrl
 |-  ( ( ( A e. No /\ B e. No ) /\ ( ( bday ` A ) = ( bday ` B ) /\ A  |^| { a e. On | ( A ` a ) =/= ( B ` a ) } e. On )
4 noreson
 |-  ( ( A e. No /\ |^| { a e. On | ( A ` a ) =/= ( B ` a ) } e. On ) -> ( A |` |^| { a e. On | ( A ` a ) =/= ( B ` a ) } ) e. No )
5 1 3 4 syl2anc
 |-  ( ( ( A e. No /\ B e. No ) /\ ( ( bday ` A ) = ( bday ` B ) /\ A  ( A |` |^| { a e. On | ( A ` a ) =/= ( B ` a ) } ) e. No )