Database
ZF (ZERMELO-FRAENKEL) SET THEORY
ZF Set Theory - add the Axiom of Union
Ordinal arithmetic
df-2o
Next ⟩
df-3o
Metamath Proof Explorer
Ascii
Unicode
Definition
df-2o
Description:
Define the ordinal number 2.
(Contributed by
NM
, 18-Feb-2004)
Ref
Expression
Assertion
df-2o
⊢
2
𝑜
=
suc
⁡
1
𝑜
Detailed syntax breakdown
Step
Hyp
Ref
Expression
0
c2o
class
2
𝑜
1
c1o
class
1
𝑜
2
1
csuc
class
suc
⁡
1
𝑜
3
0
2
wceq
wff
2
𝑜
=
suc
⁡
1
𝑜