Theorem baseid

Description: Utility theorem: index-independent form of df-base . (Contributed by NM, 20-Oct-2012)

	Ref	Expression
Assertion	baseid	⊢ Base = Slot ( Base ‘ ndx )

Proof

Step	Hyp	Ref	Expression
1		df-base	⊢ Base = Slot 1
2		1nn	⊢ 1 ∈ ℕ
3	1 2	ndxid	⊢ Base = Slot ( Base ‘ ndx )