Metamath Proof Explorer


Theorem scottabf

Description: Value of the Scott operation at a class abstraction. Variant of scottab with a nonfreeness hypothesis instead of a disjoint variable condition. (Contributed by Rohan Ridenour, 14-Aug-2023)

Ref Expression
Hypotheses scottabf.1 xψ
scottabf.2 x=yφψ
Assertion scottabf Scottx|φ=x|φyψrankxranky

Proof

Step Hyp Ref Expression
1 scottabf.1 xψ
2 scottabf.2 x=yφψ
3 df-scott Scottx|φ=zx|φ|wx|φrankzrankw
4 df-rab zx|φ|wx|φrankzrankw=z|zx|φwx|φrankzrankw
5 eqabcb z|zx|φwx|φrankzrankw=x|φyψrankxrankyzzx|φwx|φrankzrankwzx|φyψrankxranky
6 nfsab1 xzx|φ
7 nfab1 _xx|φ
8 nfv xrankzrankw
9 7 8 nfralw xwx|φrankzrankw
10 6 9 nfan xzx|φwx|φrankzrankw
11 vex zV
12 abid xx|φφ
13 eleq1w x=zxx|φzx|φ
14 12 13 bitr3id x=zφzx|φ
15 df-clab yx|φyxφ
16 1 2 sbiev yxφψ
17 15 16 bitr2i ψyx|φ
18 eleq1w y=wyx|φwx|φ
19 17 18 bitrid y=wψwx|φ
20 19 adantl x=zy=wψwx|φ
21 simpl x=zy=wx=z
22 21 fveq2d x=zy=wrankx=rankz
23 simpr x=zy=wy=w
24 23 fveq2d x=zy=wranky=rankw
25 22 24 sseq12d x=zy=wrankxrankyrankzrankw
26 20 25 imbi12d x=zy=wψrankxrankywx|φrankzrankw
27 26 cbvaldvaw x=zyψrankxrankywwx|φrankzrankw
28 df-ral wx|φrankzrankwwwx|φrankzrankw
29 27 28 bitr4di x=zyψrankxrankywx|φrankzrankw
30 14 29 anbi12d x=zφyψrankxrankyzx|φwx|φrankzrankw
31 10 11 30 elabf zx|φyψrankxrankyzx|φwx|φrankzrankw
32 31 bicomi zx|φwx|φrankzrankwzx|φyψrankxranky
33 5 32 mpgbir z|zx|φwx|φrankzrankw=x|φyψrankxranky
34 3 4 33 3eqtri Scottx|φ=x|φyψrankxranky