Definition df-3o 6386

Description: Define the ordinal number 3. (Contributed by Mario Carneiro, 14-Jul-2013.)

Assertion

Ref	Expression
df-3o	⊢ 3o = suc 2o

Detailed syntax breakdown of Definition df-3o

Step	Hyp	Ref	Expression
1		c3o 6379	. 2 class 3o
2		c2o 6378	. . 3 class 2o
3	2	csuc 4343	. 2 class suc 2o
4	1, 3	wceq 1343	1 wff 3o = suc 2o

This definition is referenced by:  3on  6395  3onn  6490  pw1ne3  7186  pw1nel3  7187  sucpw1nel3  7189  3nelsucpw1  7190  3nsssucpw1  7192  onntri35  7193  hash3  10726