Metamath Proof Explorer


Definition df-7

Description: Define the number 7. (Contributed by NM, 27-May-1999)

Ref Expression
Assertion df-7 7 = ( 6 + 1 )

Detailed syntax breakdown

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 )