Theorem pw1on 7487

Description: The power set of 1_o is an ordinal. (Contributed by Jim Kingdon, 29-Jul-2024.)

Assertion

Ref	Expression
pw1on	⊢ 𝒫 1o ∈ On

Proof of Theorem pw1on

Dummy variables 𝑥 𝑦 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		df1o2 6639	. . . . . 6 ⊢ 1o = {∅}
2		elsni 3691	. . . . . . . 8 ⊢ (𝑥 ∈ {∅} → 𝑥 = ∅)
3		0elpw 4260	. . . . . . . 8 ⊢ ∅ ∈ 𝒫 1o
4	2, 3	eqeltrdi 2322	. . . . . . 7 ⊢ (𝑥 ∈ {∅} → 𝑥 ∈ 𝒫 1o)
5	4	ssriv 3232	. . . . . 6 ⊢ {∅} ⊆ 𝒫 1o
6	1, 5	eqsstri 3260	. . . . 5 ⊢ 1o ⊆ 𝒫 1o
7		sspwb 4314	. . . . 5 ⊢ (1o ⊆ 𝒫 1o ↔ 𝒫 1o ⊆ 𝒫 𝒫 1o)
8	6, 7	mpbi 145	. . . 4 ⊢ 𝒫 1o ⊆ 𝒫 𝒫 1o
9		dftr4 4197	. . . 4 ⊢ (Tr 𝒫 1o ↔ 𝒫 1o ⊆ 𝒫 𝒫 1o)
10	8, 9	mpbir 146	. . 3 ⊢ Tr 𝒫 1o
11		elpwi 3665	. . . . . . . . 9 ⊢ (𝑥 ∈ 𝒫 1o → 𝑥 ⊆ 1o)
12	11	sselda 3228	. . . . . . . 8 ⊢ ((𝑥 ∈ 𝒫 1o ∧ 𝑦 ∈ 𝑥) → 𝑦 ∈ 1o)
13		el1o 6648	. . . . . . . 8 ⊢ (𝑦 ∈ 1o ↔ 𝑦 = ∅)
14	12, 13	sylib 122	. . . . . . 7 ⊢ ((𝑥 ∈ 𝒫 1o ∧ 𝑦 ∈ 𝑥) → 𝑦 = ∅)
15		0ss 3535	. . . . . . 7 ⊢ ∅ ⊆ 𝑥
16	14, 15	eqsstrdi 3280	. . . . . 6 ⊢ ((𝑥 ∈ 𝒫 1o ∧ 𝑦 ∈ 𝑥) → 𝑦 ⊆ 𝑥)
17	16	ralrimiva 2606	. . . . 5 ⊢ (𝑥 ∈ 𝒫 1o → ∀𝑦 ∈ 𝑥 𝑦 ⊆ 𝑥)
18		dftr3 4196	. . . . 5 ⊢ (Tr 𝑥 ↔ ∀𝑦 ∈ 𝑥 𝑦 ⊆ 𝑥)
19	17, 18	sylibr 134	. . . 4 ⊢ (𝑥 ∈ 𝒫 1o → Tr 𝑥)
20	19	rgen 2586	. . 3 ⊢ ∀𝑥 ∈ 𝒫 1oTr 𝑥
21		dford3 4470	. . 3 ⊢ (Ord 𝒫 1o ↔ (Tr 𝒫 1o ∧ ∀𝑥 ∈ 𝒫 1oTr 𝑥))
22	10, 20, 21	mpbir2an 951	. 2 ⊢ Ord 𝒫 1o
23		1oex 6633	. . 3 ⊢ 1o ∈ V
24	23	pwex 4279	. 2 ⊢ 𝒫 1o ∈ V
25		elon2 4479	. 2 ⊢ (𝒫 1o ∈ On ↔ (Ord 𝒫 1o ∧ 𝒫 1o ∈ V))
26	22, 24, 25	mpbir2an 951	1 ⊢ 𝒫 1o ∈ On

Syntax hints:   ∧ wa 104   = wceq 1398   ∈ wcel 2202  ∀wral 2511  Vcvv 2803   ⊆ wss 3201  ∅c0 3496  𝒫 cpw 3656  {csn 3673  Tr wtr 4192  Ord word 4465  Oncon0 4466  1_oc1o 6618

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 619  ax-in2 620  ax-io 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-13 2204  ax-14 2205  ax-ext 2213  ax-sep 4212  ax-nul 4220  ax-pow 4270  ax-pr 4305  ax-un 4536

This theorem depends on definitions:  df-bi 117  df-tru 1401  df-nf 1510  df-sb 1811  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2364  df-ral 2516  df-rex 2517  df-v 2805  df-dif 3203  df-un 3205  df-in 3207  df-ss 3214  df-nul 3497  df-pw 3658  df-sn 3679  df-pr 3680  df-uni 3899  df-tr 4193  df-iord 4469  df-on 4471  df-suc 4474  df-1o 6625

This theorem is referenced by:  pw1ne1  7490  sucpw1nss3  7496  onntri35  7498  onntri45  7502