Theorem nninfisollemne 7471

Description: Lemma for nninfisol 7473. A case where 𝑁 is a successor and 𝑁 and 𝑋 are not equal. (Contributed by Jim Kingdon, 13-Sep-2024.)

Hypotheses

Ref	Expression
nninfisol.x	⊢ (𝜑 → 𝑋 ∈ ℕ∞)
nninfisol.0	⊢ (𝜑 → (𝑋‘𝑁) = ∅)
nninfisol.n	⊢ (𝜑 → 𝑁 ∈ ω)
nninfisollemne.s	⊢ (𝜑 → 𝑁 ≠ ∅)
nninfisollemne.0	⊢ (𝜑 → (𝑋‘∪ 𝑁) = ∅)

Assertion

Ref	Expression
nninfisollemne	⊢ (𝜑 → DECID (𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅)) = 𝑋)

Distinct variable group:   𝑖,𝑁

Allowed substitution hints:   𝜑(𝑖)   𝑋(𝑖)

Proof of Theorem nninfisollemne

Step	Hyp	Ref	Expression
1		nninfisollemne.0	. . . . 5 ⊢ (𝜑 → (𝑋‘∪ 𝑁) = ∅)
2	1	adantr 276	. . . 4 ⊢ ((𝜑 ∧ (𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅)) = 𝑋) → (𝑋‘∪ 𝑁) = ∅)
3		simpr 110	. . . . . . . 8 ⊢ ((𝜑 ∧ (𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅)) = 𝑋) → (𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅)) = 𝑋)
4	3	fveq1d 5697	. . . . . . 7 ⊢ ((𝜑 ∧ (𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅)) = 𝑋) → ((𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅))‘∪ 𝑁) = (𝑋‘∪ 𝑁))
5		eqid 2238	. . . . . . . . . 10 ⊢ (𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅)) = (𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅))
6		eleq1 2301	. . . . . . . . . . 11 ⊢ (𝑖 = ∪ 𝑁 → (𝑖 ∈ 𝑁 ↔ ∪ 𝑁 ∈ 𝑁))
7	6	ifbid 3662	. . . . . . . . . 10 ⊢ (𝑖 = ∪ 𝑁 → if(𝑖 ∈ 𝑁, 1o, ∅) = if(∪ 𝑁 ∈ 𝑁, 1o, ∅))
8		nninfisol.n	. . . . . . . . . . 11 ⊢ (𝜑 → 𝑁 ∈ ω)
9		nnpredcl 4770	. . . . . . . . . . 11 ⊢ (𝑁 ∈ ω → ∪ 𝑁 ∈ ω)
10	8, 9	syl 14	. . . . . . . . . 10 ⊢ (𝜑 → ∪ 𝑁 ∈ ω)
11		nninfisollemne.s	. . . . . . . . . . . . 13 ⊢ (𝜑 → 𝑁 ≠ ∅)
12		nnpredlt 4771	. . . . . . . . . . . . 13 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≠ ∅) → ∪ 𝑁 ∈ 𝑁)
13	8, 11, 12	syl2anc 415	. . . . . . . . . . . 12 ⊢ (𝜑 → ∪ 𝑁 ∈ 𝑁)
14	13	iftrued 3647	. . . . . . . . . . 11 ⊢ (𝜑 → if(∪ 𝑁 ∈ 𝑁, 1o, ∅) = 1o)
15		1lt2o 6715	. . . . . . . . . . 11 ⊢ 1o ∈ 2o
16	14, 15	eqeltrdi 2329	. . . . . . . . . 10 ⊢ (𝜑 → if(∪ 𝑁 ∈ 𝑁, 1o, ∅) ∈ 2o)
17	5, 7, 10, 16	fvmptd3 5799	. . . . . . . . 9 ⊢ (𝜑 → ((𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅))‘∪ 𝑁) = if(∪ 𝑁 ∈ 𝑁, 1o, ∅))
18	17, 14	eqtrd 2271	. . . . . . . 8 ⊢ (𝜑 → ((𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅))‘∪ 𝑁) = 1o)
19	18	adantr 276	. . . . . . 7 ⊢ ((𝜑 ∧ (𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅)) = 𝑋) → ((𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅))‘∪ 𝑁) = 1o)
20	4, 19	eqtr3d 2273	. . . . . 6 ⊢ ((𝜑 ∧ (𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅)) = 𝑋) → (𝑋‘∪ 𝑁) = 1o)
21		1n0 6705	. . . . . 6 ⊢ 1o ≠ ∅
22		pm13.181 2502	. . . . . 6 ⊢ (((𝑋‘∪ 𝑁) = 1o ∧ 1o ≠ ∅) → (𝑋‘∪ 𝑁) ≠ ∅)
23	20, 21, 22	sylancl 417	. . . . 5 ⊢ ((𝜑 ∧ (𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅)) = 𝑋) → (𝑋‘∪ 𝑁) ≠ ∅)
24	23	neneqd 2441	. . . 4 ⊢ ((𝜑 ∧ (𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅)) = 𝑋) → ¬ (𝑋‘∪ 𝑁) = ∅)
25	2, 24	pm2.65da 671	. . 3 ⊢ (𝜑 → ¬ (𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅)) = 𝑋)
26	25	olcd 746	. 2 ⊢ (𝜑 → ((𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅)) = 𝑋 ∨ ¬ (𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅)) = 𝑋))
27		df-dc 847	. 2 ⊢ (DECID (𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅)) = 𝑋 ↔ ((𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅)) = 𝑋 ∨ ¬ (𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅)) = 𝑋))
28	26, 27	sylibr 134	1 ⊢ (𝜑 → DECID (𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑁, 1o, ∅)) = 𝑋)

This proof depends on syntax axioms:  ¬ wn 3   → wi 4   ∧ wa 104   ∨ wo 720  DECID wdc 846   = wceq 1402   ∈ wcel 2209   ≠ wne 2420  ∅c0 3520  ifcif 3638  ∪ cuni 3935   ↦ cmpt 4192  ωcom 4737  ‘cfv 5377  1_oc1o 6680  2_oc2o 6681  ℕ_∞xnninf 7459

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 623  ax-in2 624  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-sep 4249  ax-nul 4259  ax-pow 4311  ax-pr 4346  ax-un 4578  ax-iinf 4735

This proof depends on definitions:  df-bi 117  df-dc 847  df-3an 1011  df-tru 1405  df-fal 1408  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ne 2421  df-ral 2533  df-rex 2534  df-v 2823  df-sbc 3052  df-csb 3148  df-dif 3222  df-un 3224  df-in 3226  df-ss 3233  df-nul 3521  df-if 3639  df-pw 3690  df-sn 3715  df-pr 3716  df-op 3718  df-uni 3936  df-int 3971  df-br 4131  df-opab 4193  df-mpt 4194  df-tr 4230  df-id 4438  df-iord 4511  df-on 4513  df-suc 4516  df-iom 4738  df-xp 4780  df-rel 4781  df-cnv 4782  df-co 4783  df-dm 4784  df-iota 5337  df-fun 5379  df-fv 5385  df-1o 6687  df-2o 6688

This theorem is used by:  nninfisol  7473