Theorem 8onn

Description: The ordinal 8 is a natural number. (Contributed by BTernaryTau, 4-Sep-2026)

	Ref	Expression
Assertion	8onn	Could not format assertion : No typesetting found for |- 8o e. _om with typecode |-

Proof

Step	Hyp	Ref	Expression
1		df-8o	Could not format 8o = suc 7o : No typesetting found for |- 8o = suc 7o with typecode |-
2		7onn	Could not format 7o e. _om : No typesetting found for |- 7o e. _om with typecode |-
3		peano2	Could not format ( 7o e. _om -> suc 7o e. _om ) : No typesetting found for |- ( 7o e. _om -> suc 7o e. _om ) with typecode |-
4	2 3	ax-mp	Could not format suc 7o e. _om : No typesetting found for |- suc 7o e. _om with typecode |-
5	1 4	eqeltri	Could not format 8o e. _om : No typesetting found for |- 8o e. _om with typecode |-