Theorem bnj1098 34981

Description: First-order logic and set theory. (Contributed by Jonathan Ben-Naim, 3-Jun-2011.) (New usage is discouraged.)

Hypothesis

Ref	Expression
bnj1098.1	⊢ 𝐷 = (ω ∖ {∅})

Assertion

Ref	Expression
bnj1098	⊢ ∃𝑗((𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷) → (𝑗 ∈ 𝑛 ∧ 𝑖 = suc 𝑗))

Distinct variable groups:   𝐷,𝑗   𝑖,𝑗   𝑗,𝑛

Allowed substitution hints:   𝐷(𝑖,𝑛)

Proof of Theorem bnj1098

Step	Hyp	Ref	Expression
1		3anrev 1107	. . . . . . 7 ⊢ ((𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷) ↔ (𝑛 ∈ 𝐷 ∧ 𝑖 ∈ 𝑛 ∧ 𝑖 ≠ ∅))
2		df-3an 1095	. . . . . . 7 ⊢ ((𝑛 ∈ 𝐷 ∧ 𝑖 ∈ 𝑛 ∧ 𝑖 ≠ ∅) ↔ ((𝑛 ∈ 𝐷 ∧ 𝑖 ∈ 𝑛) ∧ 𝑖 ≠ ∅))
3	1, 2	bitri 277	. . . . . 6 ⊢ ((𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷) ↔ ((𝑛 ∈ 𝐷 ∧ 𝑖 ∈ 𝑛) ∧ 𝑖 ≠ ∅))
4		simpr 486	. . . . . . . 8 ⊢ ((𝑛 ∈ 𝐷 ∧ 𝑖 ∈ 𝑛) → 𝑖 ∈ 𝑛)
5		bnj1098.1	. . . . . . . . . 10 ⊢ 𝐷 = (ω ∖ {∅})
6	5	bnj923 34966	. . . . . . . . 9 ⊢ (𝑛 ∈ 𝐷 → 𝑛 ∈ ω)
7	6	adantr 482	. . . . . . . 8 ⊢ ((𝑛 ∈ 𝐷 ∧ 𝑖 ∈ 𝑛) → 𝑛 ∈ ω)
8		elnn 7821	. . . . . . . 8 ⊢ ((𝑖 ∈ 𝑛 ∧ 𝑛 ∈ ω) → 𝑖 ∈ ω)
9	4, 7, 8	syl2anc 591	. . . . . . 7 ⊢ ((𝑛 ∈ 𝐷 ∧ 𝑖 ∈ 𝑛) → 𝑖 ∈ ω)
10	9	anim1i 622	. . . . . 6 ⊢ (((𝑛 ∈ 𝐷 ∧ 𝑖 ∈ 𝑛) ∧ 𝑖 ≠ ∅) → (𝑖 ∈ ω ∧ 𝑖 ≠ ∅))
11	3, 10	sylbi 219	. . . . 5 ⊢ ((𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷) → (𝑖 ∈ ω ∧ 𝑖 ≠ ∅))
12		nnsuc 7828	. . . . 5 ⊢ ((𝑖 ∈ ω ∧ 𝑖 ≠ ∅) → ∃𝑗 ∈ ω 𝑖 = suc 𝑗)
13	11, 12	syl 17	. . . 4 ⊢ ((𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷) → ∃𝑗 ∈ ω 𝑖 = suc 𝑗)
14		df-rex 3066	. . . . . 6 ⊢ (∃𝑗 ∈ ω 𝑖 = suc 𝑗 ↔ ∃𝑗(𝑗 ∈ ω ∧ 𝑖 = suc 𝑗))
15	14	imbi2i 338	. . . . 5 ⊢ (((𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷) → ∃𝑗 ∈ ω 𝑖 = suc 𝑗) ↔ ((𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷) → ∃𝑗(𝑗 ∈ ω ∧ 𝑖 = suc 𝑗)))
16		19.37v 2005	. . . . 5 ⊢ (∃𝑗((𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷) → (𝑗 ∈ ω ∧ 𝑖 = suc 𝑗)) ↔ ((𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷) → ∃𝑗(𝑗 ∈ ω ∧ 𝑖 = suc 𝑗)))
17	15, 16	bitr4i 280	. . . 4 ⊢ (((𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷) → ∃𝑗 ∈ ω 𝑖 = suc 𝑗) ↔ ∃𝑗((𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷) → (𝑗 ∈ ω ∧ 𝑖 = suc 𝑗)))
18	13, 17	mpbi 232	. . 3 ⊢ ∃𝑗((𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷) → (𝑗 ∈ ω ∧ 𝑖 = suc 𝑗))
19		ancr 552	. . 3 ⊢ (((𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷) → (𝑗 ∈ ω ∧ 𝑖 = suc 𝑗)) → ((𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷) → ((𝑗 ∈ ω ∧ 𝑖 = suc 𝑗) ∧ (𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷))))
20	18, 19	bnj101 34921	. 2 ⊢ ∃𝑗((𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷) → ((𝑗 ∈ ω ∧ 𝑖 = suc 𝑗) ∧ (𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷)))
21		vex 3437	. . . . . 6 ⊢ 𝑗 ∈ V
22	21	bnj216 34930	. . . . 5 ⊢ (𝑖 = suc 𝑗 → 𝑗 ∈ 𝑖)
23	22	ad2antlr 734	. . . 4 ⊢ (((𝑗 ∈ ω ∧ 𝑖 = suc 𝑗) ∧ (𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷)) → 𝑗 ∈ 𝑖)
24		simpr2 1203	. . . 4 ⊢ (((𝑗 ∈ ω ∧ 𝑖 = suc 𝑗) ∧ (𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷)) → 𝑖 ∈ 𝑛)
25		3simpc 1157	. . . . . . 7 ⊢ ((𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷) → (𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷))
26	25	ancomd 463	. . . . . 6 ⊢ ((𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷) → (𝑛 ∈ 𝐷 ∧ 𝑖 ∈ 𝑛))
27	26	adantl 483	. . . . 5 ⊢ (((𝑗 ∈ ω ∧ 𝑖 = suc 𝑗) ∧ (𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷)) → (𝑛 ∈ 𝐷 ∧ 𝑖 ∈ 𝑛))
28		nnord 7818	. . . . 5 ⊢ (𝑛 ∈ ω → Ord 𝑛)
29		ordtr1 6358	. . . . 5 ⊢ (Ord 𝑛 → ((𝑗 ∈ 𝑖 ∧ 𝑖 ∈ 𝑛) → 𝑗 ∈ 𝑛))
30	27, 7, 28, 29	4syl 19	. . . 4 ⊢ (((𝑗 ∈ ω ∧ 𝑖 = suc 𝑗) ∧ (𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷)) → ((𝑗 ∈ 𝑖 ∧ 𝑖 ∈ 𝑛) → 𝑗 ∈ 𝑛))
31	23, 24, 30	mp2and 706	. . 3 ⊢ (((𝑗 ∈ ω ∧ 𝑖 = suc 𝑗) ∧ (𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷)) → 𝑗 ∈ 𝑛)
32		simplr 775	. . 3 ⊢ (((𝑗 ∈ ω ∧ 𝑖 = suc 𝑗) ∧ (𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷)) → 𝑖 = suc 𝑗)
33	31, 32	jca 517	. 2 ⊢ (((𝑗 ∈ ω ∧ 𝑖 = suc 𝑗) ∧ (𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷)) → (𝑗 ∈ 𝑛 ∧ 𝑖 = suc 𝑗))
34	20, 33	bnj1023 34978	1 ⊢ ∃𝑗((𝑖 ≠ ∅ ∧ 𝑖 ∈ 𝑛 ∧ 𝑛 ∈ 𝐷) → (𝑗 ∈ 𝑛 ∧ 𝑖 = suc 𝑗))

Syntax hints:   → wi 4   ∧ wa 397   ∧ w3a 1093   = wceq 1548  ∃wex 1787   ∈ wcel 2121   ≠ wne 2936  ∃wrex 3065   ∖ cdif 3882  ∅c0 4264  {csn 4558  Ord word 6313  suc csuc 6316  ωcom 7810

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1803  ax-4 1817  ax-5 1918  ax-6 1975  ax-7 2016  ax-8 2123  ax-9 2131  ax-ext 2713  ax-sep 5221  ax-nul 5231  ax-pr 5365  ax-un 7682

This theorem depends on definitions:  df-bi 209  df-an 398  df-or 855  df-3or 1094  df-3an 1095  df-tru 1551  df-fal 1561  df-ex 1788  df-sb 2075  df-clab 2720  df-cleq 2733  df-clel 2816  df-ne 2937  df-ral 3056  df-rex 3066  df-rab 3394  df-v 3435  df-dif 3888  df-un 3890  df-in 3892  df-ss 3902  df-pss 3905  df-nul 4265  df-if 4458  df-pw 4534  df-sn 4559  df-pr 4561  df-op 4565  df-uni 4842  df-br 5076  df-opab 5138  df-tr 5183  df-eprel 5521  df-po 5529  df-so 5530  df-fr 5574  df-we 5576  df-ord 6317  df-on 6318  df-lim 6319  df-suc 6320  df-om 7811

This theorem is referenced by:  bnj1110  35179  bnj1128  35187  bnj1145  35190