Metamath Proof Explorer


Definition df-2o

Description: Define the ordinal number 2. (Contributed by NM, 18-Feb-2004)

Ref Expression
Assertion df-2o
|- 2o = suc 1o

Detailed syntax breakdown

Step Hyp Ref Expression
0 c2o
 |-  2o
1 c1o
 |-  1o
2 1 csuc
 |-  suc 1o
3 0 2 wceq
 |-  2o = suc 1o