Description: Define a function that returns the third converse of a set. The third converse of a set takes all ordered triples in the set and swaps the second and third arguments. Based on Definition 14.1(2) of TakeutiZaring p. 143. (Contributed by BTernaryTau, 2-Sep-2026)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | df-cnv3 | |- Cnv3 = ( w e. _V |-> { <. <. x , y >. , z >. | <. <. x , z >. , y >. e. w } ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 0 | ccnv3 | |- Cnv3 |
|
| 1 | vw | |- w |
|
| 2 | cvv | |- _V |
|
| 3 | vx | |- x |
|
| 4 | vy | |- y |
|
| 5 | vz | |- z |
|
| 6 | 3 | cv | |- x |
| 7 | 5 | cv | |- z |
| 8 | 6 7 | cop | |- <. x , z >. |
| 9 | 4 | cv | |- y |
| 10 | 8 9 | cop | |- <. <. x , z >. , y >. |
| 11 | 1 | cv | |- w |
| 12 | 10 11 | wcel | |- <. <. x , z >. , y >. e. w |
| 13 | 12 3 4 5 | coprab | |- { <. <. x , y >. , z >. | <. <. x , z >. , y >. e. w } |
| 14 | 1 2 13 | cmpt | |- ( w e. _V |-> { <. <. x , y >. , z >. | <. <. x , z >. , y >. e. w } ) |
| 15 | 0 14 | wceq | |- Cnv3 = ( w e. _V |-> { <. <. x , y >. , z >. | <. <. x , z >. , y >. e. w } ) |