Metamath Proof Explorer


Theorem ipostr

Description: The structure of df-ipo is a structure defining indices up to 11. (Contributed by Mario Carneiro, 25-Oct-2015)

Ref Expression
Assertion ipostr ⊢ Base ndx B TopSet ⁡ ndx J ∪ ≤ ndx ≤ ˙ oc ⁡ ndx ⊥ ˙ Struct 1 11

Proof

Step Hyp Ref Expression
1 1nn ⊢ 1 ∈ ℕ
2 basendx ⊢ Base ndx = 1
3 1lt9 ⊢ 1 < 9
4 9nn ⊢ 9 ∈ ℕ
5 tsetndx ⊢ TopSet ⁡ ndx = 9
6 1 2 3 4 5 strle2 ⊢ Base ndx B TopSet ⁡ ndx J Struct 1 9
7 10nn ⊢ 10 ∈ ℕ
8 plendx ⊢ ≤ ndx = 10
9 1nn0 ⊢ 1 ∈ ℕ 0
10 0nn0 ⊢ 0 ∈ ℕ 0
11 0lt1 ⊢ 0 < 1
12 9 10 1 11 declt ⊢ 10 < 11
13 9 1 decnncl ⊢ 11 ∈ ℕ
14 ocndx ⊢ oc ⁡ ndx = 11
15 7 8 12 13 14 strle2 ⊢ ≤ ndx ≤ ˙ oc ⁡ ndx ⊥ ˙ Struct 10 11
16 9lt10 ⊢ 9 < 10
17 6 15 16 strleun ⊢ Base ndx B TopSet ⁡ ndx J ∪ ≤ ndx ≤ ˙ oc ⁡ ndx ⊥ ˙ Struct 1 11