Metamath Proof Explorer


Theorem nfriotadw

Description: Deduction version of nfriota with a disjoint variable condition, which contrary to nfriotad does not require ax-13 . (Contributed by NM, 18-Feb-2013) Avoid ax-13 . (Revised by Gino Giotto, 26-Jan-2024)

Ref Expression
Hypotheses nfriotadw.1 yφ
nfriotadw.2 φxψ
nfriotadw.3 φ_xA
Assertion nfriotadw φ_xιyA|ψ

Proof

Step Hyp Ref Expression
1 nfriotadw.1 yφ
2 nfriotadw.2 φxψ
3 nfriotadw.3 φ_xA
4 df-riota ιyA|ψ=ιy|yAψ
5 nfnaew y¬xx=y
6 1 5 nfan yφ¬xx=y
7 nfcvd ¬xx=y_xy
8 7 adantl φ¬xx=y_xy
9 3 adantr φ¬xx=y_xA
10 8 9 nfeld φ¬xx=yxyA
11 2 adantr φ¬xx=yxψ
12 10 11 nfand φ¬xx=yxyAψ
13 6 12 nfiotadw φ¬xx=y_xιy|yAψ
14 13 ex φ¬xx=y_xιy|yAψ
15 nfiota1 _yιy|yAψ
16 biidd xx=ywιy|yAψwιy|yAψ
17 16 drnf1v xx=yxwιy|yAψywιy|yAψ
18 17 albidv xx=ywxwιy|yAψwywιy|yAψ
19 df-nfc _xιy|yAψwxwιy|yAψ
20 df-nfc _yιy|yAψwywιy|yAψ
21 18 19 20 3bitr4g xx=y_xιy|yAψ_yιy|yAψ
22 15 21 mpbiri xx=y_xιy|yAψ
23 14 22 pm2.61d2 φ_xιy|yAψ
24 4 23 nfcxfrd φ_xιyA|ψ