Theorem 3nelsucpw1 7380

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 6551	. . . . 5 ⊢ 1o ∈ 2o
2		elelsuc 4474	. . . . 5 ⊢ (1o ∈ 2o → 1o ∈ suc 2o)
3	1, 2	ax-mp 5	. . . 4 ⊢ 1o ∈ suc 2o
4		df-3o 6527	. . . 4 ⊢ 3o = suc 2o
5	3, 4	eleqtrri 2283	. . 3 ⊢ 1o ∈ 3o
6		ssnel 4635	. . 3 ⊢ (3o ⊆ 1o → ¬ 1o ∈ 3o)
7	5, 6	mt2 641	. 2 ⊢ ¬ 3o ⊆ 1o
8		pw1ne3 7376	. . . . . 6 ⊢ 𝒫 1o ≠ 3o
9	8	nesymi 2424	. . . . 5 ⊢ ¬ 3o = 𝒫 1o
10	9	a1i 9	. . . 4 ⊢ (3o ∈ suc 𝒫 1o → ¬ 3o = 𝒫 1o)
11		elsuci 4468	. . . 4 ⊢ (3o ∈ suc 𝒫 1o → (3o ∈ 𝒫 1o ∨ 3o = 𝒫 1o))
12	10, 11	ecased 1362	. . 3 ⊢ (3o ∈ suc 𝒫 1o → 3o ∈ 𝒫 1o)
13	12	elpwid 3637	. 2 ⊢ (3o ∈ suc 𝒫 1o → 3o ⊆ 1o)
14	7, 13	mto 664	1 ⊢ ¬ 3o ∈ suc 𝒫 1o

Syntax hints:  ¬ wn 3   = wceq 1373   ∈ wcel 2178   ⊆ wss 3174  𝒫 cpw 3626  suc csuc 4430  1_oc1o 6518  2_oc2o 6519  3_oc3o 6520

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 615  ax-in2 616  ax-io 711  ax-5 1471  ax-7 1472  ax-gen 1473  ax-ie1 1517  ax-ie2 1518  ax-8 1528  ax-10 1529  ax-11 1530  ax-i12 1531  ax-bndl 1533  ax-4 1534  ax-17 1550  ax-i9 1554  ax-ial 1558  ax-i5r 1559  ax-13 2180  ax-14 2181  ax-ext 2189  ax-sep 4178  ax-nul 4186  ax-pow 4234  ax-pr 4269  ax-un 4498  ax-setind 4603

This theorem depends on definitions:  df-bi 117  df-3an 983  df-tru 1376  df-nf 1485  df-sb 1787  df-clab 2194  df-cleq 2200  df-clel 2203  df-nfc 2339  df-ne 2379  df-ral 2491  df-rex 2492  df-v 2778  df-dif 3176  df-un 3178  df-in 3180  df-ss 3187  df-nul 3469  df-pw 3628  df-sn 3649  df-pr 3650  df-uni 3865  df-int 3900  df-tr 4159  df-iord 4431  df-on 4433  df-suc 4436  df-iom 4657  df-1o 6525  df-2o 6526  df-3o 6527

This theorem is referenced by:  onntri35  7383