Definition df-1o 6024

Description: Define the ordinal number 1. (Contributed by NM, 29-Oct-1995.)

Assertion

Ref	Expression
df-1o	⊢ 1𝑜 = suc ∅

Detailed syntax breakdown of Definition df-1o

Step	Hyp	Ref	Expression
1		c1o 6017	. 2 class 1𝑜
2		c0 3251	. . 3 class ∅
3	2	csuc 4120	. 2 class suc ∅
4	1, 3	wceq 1284	1 wff 1𝑜 = suc ∅

This definition is referenced by:  1on  6031  df1o2  6036  ordgt0ge1  6041  oa1suc  6070  1onn  6116  nnm1  6120  nlt1pig  6531  indpi  6532