Metamath Proof Explorer


Theorem unifndxnbasendx

Description: The slot for the uniform set is not the slot for the base set in an extensible structure. (Contributed by AV, 21-Oct-2024)

Ref Expression
Assertion unifndxnbasendx
|- ( UnifSet ` ndx ) =/= ( Base ` ndx )

Proof

Step Hyp Ref Expression
1 1re
 |-  1 e. RR
2 1nn
 |-  1 e. NN
3 3nn0
 |-  3 e. NN0
4 1nn0
 |-  1 e. NN0
5 1lt10
 |-  1 < ; 1 0
6 2 3 4 5 declti
 |-  1 < ; 1 3
7 1 6 gtneii
 |-  ; 1 3 =/= 1
8 unifndx
 |-  ( UnifSet ` ndx ) = ; 1 3
9 basendx
 |-  ( Base ` ndx ) = 1
10 8 9 neeq12i
 |-  ( ( UnifSet ` ndx ) =/= ( Base ` ndx ) <-> ; 1 3 =/= 1 )
11 7 10 mpbir
 |-  ( UnifSet ` ndx ) =/= ( Base ` ndx )