Metamath Proof Explorer


Theorem nfscott

Description: Bound-variable hypothesis builder for the Scott operation. (Contributed by Rohan Ridenour, 11-Aug-2023)

Ref Expression
Hypothesis nfscott.1
|- F/_ x A
Assertion nfscott
|- F/_ x Scott A

Proof

Step Hyp Ref Expression
1 nfscott.1
 |-  F/_ x A
2 df-scott
 |-  Scott A = { y e. A | A. z e. A ( rank ` y ) C_ ( rank ` z ) }
3 nfv
 |-  F/ x ( rank ` y ) C_ ( rank ` z )
4 1 3 nfralw
 |-  F/ x A. z e. A ( rank ` y ) C_ ( rank ` z )
5 4 1 nfrabw
 |-  F/_ x { y e. A | A. z e. A ( rank ` y ) C_ ( rank ` z ) }
6 2 5 nfcxfr
 |-  F/_ x Scott A