Metamath Proof Explorer


Definition df-8

Description: Define the number 8. (Contributed by NM, 27-May-1999)

Ref Expression
Assertion df-8 8 = 7 + 1

Detailed syntax breakdown

Step Hyp Ref Expression
0 c8 class 8
1 c7 class 7
2 caddc class +
3 c1 class 1
4 1 3 2 co class 7 + 1
5 0 4 wceq wff 8 = 7 + 1