Metamath Proof Explorer


Theorem nnneo

Description: If a natural number is even, its successor is odd. (Contributed by Mario Carneiro, 16-Nov-2014)

Ref Expression
Assertion nnneo AωBωC=2𝑜𝑜A¬sucC=2𝑜𝑜B

Proof

Step Hyp Ref Expression
1 nnon AωAOn
2 onnbtwn AOn¬ABBsucA
3 1 2 syl Aω¬ABBsucA
4 3 3ad2ant1 AωBωC=2𝑜𝑜A¬ABBsucA
5 suceq C=2𝑜𝑜AsucC=suc2𝑜𝑜A
6 5 eqeq1d C=2𝑜𝑜AsucC=2𝑜𝑜Bsuc2𝑜𝑜A=2𝑜𝑜B
7 6 3ad2ant3 AωBωC=2𝑜𝑜AsucC=2𝑜𝑜Bsuc2𝑜𝑜A=2𝑜𝑜B
8 ovex 2𝑜𝑜AV
9 8 sucid 2𝑜𝑜Asuc2𝑜𝑜A
10 eleq2 suc2𝑜𝑜A=2𝑜𝑜B2𝑜𝑜Asuc2𝑜𝑜A2𝑜𝑜A2𝑜𝑜B
11 9 10 mpbii suc2𝑜𝑜A=2𝑜𝑜B2𝑜𝑜A2𝑜𝑜B
12 2onn 2𝑜ω
13 nnmord AωBω2𝑜ωAB2𝑜2𝑜𝑜A2𝑜𝑜B
14 12 13 mp3an3 AωBωAB2𝑜2𝑜𝑜A2𝑜𝑜B
15 simpl AB2𝑜AB
16 14 15 syl6bir AωBω2𝑜𝑜A2𝑜𝑜BAB
17 11 16 syl5 AωBωsuc2𝑜𝑜A=2𝑜𝑜BAB
18 simpr AωBωsuc2𝑜𝑜A=2𝑜𝑜Bsuc2𝑜𝑜A=2𝑜𝑜B
19 nnmcl 2𝑜ωAω2𝑜𝑜Aω
20 12 19 mpan Aω2𝑜𝑜Aω
21 nnon 2𝑜𝑜Aω2𝑜𝑜AOn
22 oa1suc 2𝑜𝑜AOn2𝑜𝑜A+𝑜1𝑜=suc2𝑜𝑜A
23 20 21 22 3syl Aω2𝑜𝑜A+𝑜1𝑜=suc2𝑜𝑜A
24 1oex 1𝑜V
25 24 sucid 1𝑜suc1𝑜
26 df-2o 2𝑜=suc1𝑜
27 25 26 eleqtrri 1𝑜2𝑜
28 1onn 1𝑜ω
29 nnaord 1𝑜ω2𝑜ω2𝑜𝑜Aω1𝑜2𝑜2𝑜𝑜A+𝑜1𝑜2𝑜𝑜A+𝑜2𝑜
30 28 12 20 29 mp3an12i Aω1𝑜2𝑜2𝑜𝑜A+𝑜1𝑜2𝑜𝑜A+𝑜2𝑜
31 27 30 mpbii Aω2𝑜𝑜A+𝑜1𝑜2𝑜𝑜A+𝑜2𝑜
32 nnmsuc 2𝑜ωAω2𝑜𝑜sucA=2𝑜𝑜A+𝑜2𝑜
33 12 32 mpan Aω2𝑜𝑜sucA=2𝑜𝑜A+𝑜2𝑜
34 31 33 eleqtrrd Aω2𝑜𝑜A+𝑜1𝑜2𝑜𝑜sucA
35 23 34 eqeltrrd Aωsuc2𝑜𝑜A2𝑜𝑜sucA
36 35 ad2antrr AωBωsuc2𝑜𝑜A=2𝑜𝑜Bsuc2𝑜𝑜A2𝑜𝑜sucA
37 18 36 eqeltrrd AωBωsuc2𝑜𝑜A=2𝑜𝑜B2𝑜𝑜B2𝑜𝑜sucA
38 peano2 AωsucAω
39 nnmord BωsucAω2𝑜ωBsucA2𝑜2𝑜𝑜B2𝑜𝑜sucA
40 12 39 mp3an3 BωsucAωBsucA2𝑜2𝑜𝑜B2𝑜𝑜sucA
41 38 40 sylan2 BωAωBsucA2𝑜2𝑜𝑜B2𝑜𝑜sucA
42 41 ancoms AωBωBsucA2𝑜2𝑜𝑜B2𝑜𝑜sucA
43 42 adantr AωBωsuc2𝑜𝑜A=2𝑜𝑜BBsucA2𝑜2𝑜𝑜B2𝑜𝑜sucA
44 37 43 mpbird AωBωsuc2𝑜𝑜A=2𝑜𝑜BBsucA2𝑜
45 44 simpld AωBωsuc2𝑜𝑜A=2𝑜𝑜BBsucA
46 45 ex AωBωsuc2𝑜𝑜A=2𝑜𝑜BBsucA
47 17 46 jcad AωBωsuc2𝑜𝑜A=2𝑜𝑜BABBsucA
48 47 3adant3 AωBωC=2𝑜𝑜Asuc2𝑜𝑜A=2𝑜𝑜BABBsucA
49 7 48 sylbid AωBωC=2𝑜𝑜AsucC=2𝑜𝑜BABBsucA
50 4 49 mtod AωBωC=2𝑜𝑜A¬sucC=2𝑜𝑜B