Metamath Proof Explorer


Definition df-4

Description: Define the number 4. (Contributed by NM, 27-May-1999)

Ref Expression
Assertion df-4
|- 4 = ( 3 + 1 )

Detailed syntax breakdown

Step Hyp Ref Expression
0 c4
 |-  4
1 c3
 |-  3
2 caddc
 |-  +
3 c1
 |-  1
4 1 3 2 co
 |-  ( 3 + 1 )
5 0 4 wceq
 |-  4 = ( 3 + 1 )