Theorem nntri3or 6656

Description: Trichotomy for natural numbers. (Contributed by Jim Kingdon, 25-Aug-2019.)

Assertion

Ref	Expression
nntri3or	|- ( ( A e. om /\ B e. om ) -> ( A e. B \/ A = B \/ B e. A ) )

Proof of Theorem nntri3or

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

Step	Hyp	Ref	Expression
1		eleq2 2293	. . . . 5 |- ( x = B -> ( A e. x <-> A e. B ) )
2		eqeq2 2239	. . . . 5 |- ( x = B -> ( A = x <-> A = B ) )
3		eleq1 2292	. . . . 5 |- ( x = B -> ( x e. A <-> B e. A ) )
4	1, 2, 3	3orbi123d 1345	. . . 4 |- ( x = B -> ( ( A e. x \/ A = x \/ x e. A ) <-> ( A e. B \/ A = B \/ B e. A ) ) )
5	4	imbi2d 230	. . 3 |- ( x = B -> ( ( A e. om -> ( A e. x \/ A = x \/ x e. A ) ) <-> ( A e. om -> ( A e. B \/ A = B \/ B e. A ) ) ) )
6		eleq2 2293	. . . . 5 |- ( x = (/) -> ( A e. x <-> A e. (/) ) )
7		eqeq2 2239	. . . . 5 |- ( x = (/) -> ( A = x <-> A = (/) ) )
8		eleq1 2292	. . . . 5 |- ( x = (/) -> ( x e. A <-> (/) e. A ) )
9	6, 7, 8	3orbi123d 1345	. . . 4 |- ( x = (/) -> ( ( A e. x \/ A = x \/ x e. A ) <-> ( A e. (/) \/ A = (/) \/ (/) e. A ) ) )
10		eleq2 2293	. . . . 5 |- ( x = y -> ( A e. x <-> A e. y ) )
11		eqeq2 2239	. . . . 5 |- ( x = y -> ( A = x <-> A = y ) )
12		eleq1 2292	. . . . 5 |- ( x = y -> ( x e. A <-> y e. A ) )
13	10, 11, 12	3orbi123d 1345	. . . 4 |- ( x = y -> ( ( A e. x \/ A = x \/ x e. A ) <-> ( A e. y \/ A = y \/ y e. A ) ) )
14		eleq2 2293	. . . . 5 |- ( x = suc y -> ( A e. x <-> A e. suc y ) )
15		eqeq2 2239	. . . . 5 |- ( x = suc y -> ( A = x <-> A = suc y ) )
16		eleq1 2292	. . . . 5 |- ( x = suc y -> ( x e. A <-> suc y e. A ) )
17	14, 15, 16	3orbi123d 1345	. . . 4 |- ( x = suc y -> ( ( A e. x \/ A = x \/ x e. A ) <-> ( A e. suc y \/ A = suc y \/ suc y e. A ) ) )
18		0elnn 4715	. . . . 5 |- ( A e. om -> ( A = (/) \/ (/) e. A ) )
19		olc 716	. . . . . 6 |- ( ( A = (/) \/ (/) e. A ) -> ( A e. (/) \/ ( A = (/) \/ (/) e. A ) ) )
20		3orass 1005	. . . . . 6 |- ( ( A e. (/) \/ A = (/) \/ (/) e. A ) <-> ( A e. (/) \/ ( A = (/) \/ (/) e. A ) ) )
21	19, 20	sylibr 134	. . . . 5 |- ( ( A = (/) \/ (/) e. A ) -> ( A e. (/) \/ A = (/) \/ (/) e. A ) )
22	18, 21	syl 14	. . . 4 |- ( A e. om -> ( A e. (/) \/ A = (/) \/ (/) e. A ) )
23		df-3or 1003	. . . . . 6 |- ( ( A e. y \/ A = y \/ y e. A ) <-> ( ( A e. y \/ A = y ) \/ y e. A ) )
24		elex 2812	. . . . . . . 8 |- ( y e. om -> y e. _V )
25		elsuc2g 4500	. . . . . . . . 9 |- ( y e. _V -> ( A e. suc y <-> ( A e. y \/ A = y ) ) )
26		3mix1 1190	. . . . . . . . 9 |- ( A e. suc y -> ( A e. suc y \/ A = suc y \/ suc y e. A ) )
27	25, 26	biimtrrdi 164	. . . . . . . 8 |- ( y e. _V -> ( ( A e. y \/ A = y ) -> ( A e. suc y \/ A = suc y \/ suc y e. A ) ) )
28	24, 27	syl 14	. . . . . . 7 |- ( y e. om -> ( ( A e. y \/ A = y ) -> ( A e. suc y \/ A = suc y \/ suc y e. A ) ) )
29		nnsucelsuc 6654	. . . . . . . . 9 |- ( A e. om -> ( y e. A <-> suc y e. suc A ) )
30		elsuci 4498	. . . . . . . . 9 |- ( suc y e. suc A -> ( suc y e. A \/ suc y = A ) )
31	29, 30	biimtrdi 163	. . . . . . . 8 |- ( A e. om -> ( y e. A -> ( suc y e. A \/ suc y = A ) ) )
32		eqcom 2231	. . . . . . . . . . . . 13 |- ( suc y = A <-> A = suc y )
33	32	orbi2i 767	. . . . . . . . . . . 12 |- ( ( suc y e. A \/ suc y = A ) <-> ( suc y e. A \/ A = suc y ) )
34	33	biimpi 120	. . . . . . . . . . 11 |- ( ( suc y e. A \/ suc y = A ) -> ( suc y e. A \/ A = suc y ) )
35	34	orcomd 734	. . . . . . . . . 10 |- ( ( suc y e. A \/ suc y = A ) -> ( A = suc y \/ suc y e. A ) )
36	35	olcd 739	. . . . . . . . 9 |- ( ( suc y e. A \/ suc y = A ) -> ( A e. suc y \/ ( A = suc y \/ suc y e. A ) ) )
37		3orass 1005	. . . . . . . . 9 |- ( ( A e. suc y \/ A = suc y \/ suc y e. A ) <-> ( A e. suc y \/ ( A = suc y \/ suc y e. A ) ) )
38	36, 37	sylibr 134	. . . . . . . 8 |- ( ( suc y e. A \/ suc y = A ) -> ( A e. suc y \/ A = suc y \/ suc y e. A ) )
39	31, 38	syl6 33	. . . . . . 7 |- ( A e. om -> ( y e. A -> ( A e. suc y \/ A = suc y \/ suc y e. A ) ) )
40	28, 39	jaao 724	. . . . . 6 |- ( ( y e. om /\ A e. om ) -> ( ( ( A e. y \/ A = y ) \/ y e. A ) -> ( A e. suc y \/ A = suc y \/ suc y e. A ) ) )
41	23, 40	biimtrid 152	. . . . 5 |- ( ( y e. om /\ A e. om ) -> ( ( A e. y \/ A = y \/ y e. A ) -> ( A e. suc y \/ A = suc y \/ suc y e. A ) ) )
42	41	ex 115	. . . 4 |- ( y e. om -> ( A e. om -> ( ( A e. y \/ A = y \/ y e. A ) -> ( A e. suc y \/ A = suc y \/ suc y e. A ) ) ) )
43	9, 13, 17, 22, 42	finds2 4697	. . 3 |- ( x e. om -> ( A e. om -> ( A e. x \/ A = x \/ x e. A ) ) )
44	5, 43	vtoclga 2868	. 2 |- ( B e. om -> ( A e. om -> ( A e. B \/ A = B \/ B e. A ) ) )
45	44	impcom 125	1 |- ( ( A e. om /\ B e. om ) -> ( A e. B \/ A = B \/ B e. A ) )

Syntax hints:   -> wi 4   /\ wa 104   \/ wo 713   \/ w3o 1001   = wceq 1395   e. wcel 2200   _Vcvv 2800   (/)c0 3492   suc csuc 4460   omcom 4686

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 617  ax-in2 618  ax-io 714  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-10 1551  ax-11 1552  ax-i12 1553  ax-bndl 1555  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-13 2202  ax-14 2203  ax-ext 2211  ax-sep 4205  ax-nul 4213  ax-pow 4262  ax-pr 4297  ax-un 4528  ax-iinf 4684

This theorem depends on definitions:  df-bi 117  df-3or 1003  df-3an 1004  df-tru 1398  df-nf 1507  df-sb 1809  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-ral 2513  df-rex 2514  df-v 2802  df-dif 3200  df-un 3202  df-in 3204  df-ss 3211  df-nul 3493  df-pw 3652  df-sn 3673  df-pr 3674  df-uni 3892  df-int 3927  df-tr 4186  df-iord 4461  df-on 4463  df-suc 4466  df-iom 4687

This theorem is referenced by:  nntri2  6657  nntri1  6659  nntri3  6660  nntri2or2  6661  nndceq  6662  nndcel  6663  nnsseleq  6664  nntr2  6666  nnawordex  6692  nnwetri  7101  nnnninfeq  7318  ltsopi  7530  pitri3or  7532  frec2uzlt2d  10656  nninfctlemfo  12601  ennnfonelemk  13011  ennnfonelemex  13025