Metamath Proof Explorer


Theorem baseltedgfOLD

Description: Obsolete proof of basendxltedgfndx as of 30-Oct-2024. The index value of the Base slot is less than the index value of the .ef slot. (Contributed by AV, 21-Sep-2020) (Proof modification is discouraged.) (New usage is discouraged.)

Ref Expression
Assertion baseltedgfOLD ( Base ‘ ndx ) < ( .ef ‘ ndx )

Proof

Step Hyp Ref Expression
1 1nn 1 ∈ ℕ
2 8nn0 8 ∈ ℕ0
3 1nn0 1 ∈ ℕ0
4 1lt10 1 < 1 0
5 1 2 3 4 declti 1 < 1 8
6 df-base Base = Slot 1
7 6 1 ndxarg ( Base ‘ ndx ) = 1
8 df-edgf .ef = Slot 1 8
9 8nn 8 ∈ ℕ
10 3 9 decnncl 1 8 ∈ ℕ
11 8 10 ndxarg ( .ef ‘ ndx ) = 1 8
12 5 7 11 3brtr4i ( Base ‘ ndx ) < ( .ef ‘ ndx )