Metamath Proof Explorer


Definition df-3

Description: Define the number 3. (Contributed by NM, 27-May-1999)

Ref Expression
Assertion df-3 3 = ( 2 + 1 )

Detailed syntax breakdown

Step Hyp Ref Expression
0 c3 ⊢ 3
1 c2 ⊢ 2
2 caddc ⊢ +
3 c1 ⊢ 1
4 1 3 2 co ⊢ ( 2 + 1 )
5 0 4 wceq ⊢ 3 = ( 2 + 1 )