Description: Define the number 7. (Contributed by NM, 27-May-1999)
Ref | Expression | ||
---|---|---|---|
Assertion | df-7 | ⊢ 7 = ( 6 + 1 ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
0 | c7 | ⊢ 7 | |
1 | c6 | ⊢ 6 | |
2 | caddc | ⊢ + | |
3 | c1 | ⊢ 1 | |
4 | 1 3 2 | co | ⊢ ( 6 + 1 ) |
5 | 0 4 | wceq | ⊢ 7 = ( 6 + 1 ) |