Metamath Proof Explorer


Definition df-9o

Description: Define the ordinal number 9. (Contributed by BTernaryTau, 2-Sep-2026)

Ref Expression
Assertion df-9o Could not format assertion : No typesetting found for |- 9o = suc 8o with typecode |-

Detailed syntax breakdown

Step Hyp Ref Expression
0 c9o Could not format 9o : No typesetting found for class 9o with typecode class
1 c8o Could not format 8o : No typesetting found for class 8o with typecode class
2 1 csuc Could not format suc 8o : No typesetting found for class suc 8o with typecode class
3 0 2 wceq Could not format 9o = suc 8o : No typesetting found for wff 9o = suc 8o with typecode wff