Theorem 3nelsucpw1 7495

Description: Three is not an element of the successor of the power set of 1_o. (Contributed by James E. Hanson and Jim Kingdon, 30-Jul-2024.)

Assertion

Ref	Expression
3nelsucpw1	⊢ ¬ 3o ∈ suc 𝒫 1o

Proof of Theorem 3nelsucpw1

Step	Hyp	Ref	Expression
1		1lt2o 6653	. . . . 5 ⊢ 1o ∈ 2o
2		elelsuc 4512	. . . . 5 ⊢ (1o ∈ 2o → 1o ∈ suc 2o)
3	1, 2	ax-mp 5	. . . 4 ⊢ 1o ∈ suc 2o
4		df-3o 6627	. . . 4 ⊢ 3o = suc 2o
5	3, 4	eleqtrri 2307	. . 3 ⊢ 1o ∈ 3o
6		ssnel 4673	. . 3 ⊢ (3o ⊆ 1o → ¬ 1o ∈ 3o)
7	5, 6	mt2 645	. 2 ⊢ ¬ 3o ⊆ 1o
8		pw1ne3 7491	. . . . . 6 ⊢ 𝒫 1o ≠ 3o
9	8	nesymi 2449	. . . . 5 ⊢ ¬ 3o = 𝒫 1o
10	9	a1i 9	. . . 4 ⊢ (3o ∈ suc 𝒫 1o → ¬ 3o = 𝒫 1o)
11		elsuci 4506	. . . 4 ⊢ (3o ∈ suc 𝒫 1o → (3o ∈ 𝒫 1o ∨ 3o = 𝒫 1o))
12	10, 11	ecased 1386	. . 3 ⊢ (3o ∈ suc 𝒫 1o → 3o ∈ 𝒫 1o)
13	12	elpwid 3667	. 2 ⊢ (3o ∈ suc 𝒫 1o → 3o ⊆ 1o)
14	7, 13	mto 668	1 ⊢ ¬ 3o ∈ suc 𝒫 1o

Syntax hints:  ¬ wn 3   = wceq 1398   ∈ wcel 2202   ⊆ wss 3201  𝒫 cpw 3656  suc csuc 4468  1_oc1o 6618  2_oc2o 6619  3_oc3o 6620

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  ax-setind 4641

This theorem depends on definitions:  df-bi 117  df-3an 1007  df-tru 1401  df-nf 1510  df-sb 1811  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2364  df-ne 2404  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-int 3934  df-tr 4193  df-iord 4469  df-on 4471  df-suc 4474  df-iom 4695  df-1o 6625  df-2o 6626  df-3o 6627

This theorem is referenced by:  onntri35  7498