Description: Define the number 8. (Contributed by NM, 27-May-1999)
Ref | Expression | ||
---|---|---|---|
Assertion | df-8 | ⊢ 8 = ( 7 + 1 ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
0 | c8 | ⊢ 8 | |
1 | c7 | ⊢ 7 | |
2 | caddc | ⊢ + | |
3 | c1 | ⊢ 1 | |
4 | 1 3 2 | co | ⊢ ( 7 + 1 ) |
5 | 0 4 | wceq | ⊢ 8 = ( 7 + 1 ) |