Metamath Proof Explorer


Theorem eucrct2eupth

Description: Removing one edge ( I( FJ ) ) from a graph G with an Eulerian circuit <. F , P >. results in a graph S with an Eulerian path <. H , Q >. . (Contributed by AV, 17-Mar-2021) Hypothesis revised using the prefix operation. (Revised by AV, 30-Nov-2022)

Ref Expression
Hypotheses eucrct2eupth1.v V=VtxG
eucrct2eupth1.i I=iEdgG
eucrct2eupth1.d φFEulerPathsGP
eucrct2eupth1.c φFCircuitsGP
eucrct2eupth1.s VtxS=V
eucrct2eupth.n φN=F
eucrct2eupth.j φJ0..^N
eucrct2eupth.e φiEdgS=IF0..^NJ
eucrct2eupth.k K=J+1
eucrct2eupth.h H=FcyclShiftKprefixN1
eucrct2eupth.q Q=x0..^NifxNKPx+KPx+K-N
Assertion eucrct2eupth φHEulerPathsSQ

Proof

Step Hyp Ref Expression
1 eucrct2eupth1.v V=VtxG
2 eucrct2eupth1.i I=iEdgG
3 eucrct2eupth1.d φFEulerPathsGP
4 eucrct2eupth1.c φFCircuitsGP
5 eucrct2eupth1.s VtxS=V
6 eucrct2eupth.n φN=F
7 eucrct2eupth.j φJ0..^N
8 eucrct2eupth.e φiEdgS=IF0..^NJ
9 eucrct2eupth.k K=J+1
10 eucrct2eupth.h H=FcyclShiftKprefixN1
11 eucrct2eupth.q Q=x0..^NifxNKPx+KPx+K-N
12 3 adantl J=N1φFEulerPathsGP
13 9 eqcomi J+1=K
14 13 oveq2i FcyclShiftJ+1=FcyclShiftK
15 oveq1 J=N1J+1=N-1+1
16 elfzo0 J0..^NJ0NJ<N
17 nncn NN
18 17 3ad2ant2 J0NJ<NN
19 16 18 sylbi J0..^NN
20 npcan1 NN-1+1=N
21 7 19 20 3syl φN-1+1=N
22 15 21 sylan9eq J=N1φJ+1=N
23 22 oveq2d J=N1φFcyclShiftJ+1=FcyclShiftN
24 6 oveq2d φFcyclShiftN=FcyclShiftF
25 crctiswlk FCircuitsGPFWalksGP
26 2 wlkf FWalksGPFWorddomI
27 25 26 syl FCircuitsGPFWorddomI
28 4 27 syl φFWorddomI
29 cshwn FWorddomIFcyclShiftF=F
30 28 29 syl φFcyclShiftF=F
31 24 30 eqtrd φFcyclShiftN=F
32 31 adantl J=N1φFcyclShiftN=F
33 23 32 eqtrd J=N1φFcyclShiftJ+1=F
34 14 33 eqtr3id J=N1φFcyclShiftK=F
35 eqid F=F
36 1 2 4 35 crctcshlem1 φF0
37 fz0sn0fz1 F00F=01F
38 36 37 syl φ0F=01F
39 38 eleq2d φx0Fx01F
40 elun x01Fx0x1F
41 39 40 bitrdi φx0Fx0x1F
42 elsni x0x=0
43 0le0 00
44 42 43 eqbrtrdi x0x0
45 44 adantl φx0x0
46 45 iftrued φx0ifx0Px+NPx+N-N=Px+N
47 6 fveq2d φPN=PF
48 crctprop FCircuitsGPFTrailsGPP0=PF
49 simpr FTrailsGPP0=PFP0=PF
50 49 eqcomd FTrailsGPP0=PFPF=P0
51 4 48 50 3syl φPF=P0
52 47 51 eqtrd φPN=P0
53 52 adantr φx=0PN=P0
54 oveq1 x=0x+N=0+N
55 7 19 syl φN
56 55 addlidd φ0+N=N
57 54 56 sylan9eqr φx=0x+N=N
58 57 fveq2d φx=0Px+N=PN
59 fveq2 x=0Px=P0
60 59 adantl φx=0Px=P0
61 53 58 60 3eqtr4d φx=0Px+N=Px
62 42 61 sylan2 φx0Px+N=Px
63 46 62 eqtrd φx0ifx0Px+NPx+N-N=Px
64 63 ex φx0ifx0Px+NPx+N-N=Px
65 elfznn x1Fx
66 nnnle0 x¬x0
67 65 66 syl x1F¬x0
68 67 adantl φx1F¬x0
69 68 iffalsed φx1Fifx0Px+NPx+N-N=Px+N-N
70 65 nncnd x1Fx
71 70 adantl φx1Fx
72 55 adantr φx1FN
73 71 72 pncand φx1Fx+N-N=x
74 73 fveq2d φx1FPx+N-N=Px
75 69 74 eqtrd φx1Fifx0Px+NPx+N-N=Px
76 75 ex φx1Fifx0Px+NPx+N-N=Px
77 64 76 jaod φx0x1Fifx0Px+NPx+N-N=Px
78 41 77 sylbid φx0Fifx0Px+NPx+N-N=Px
79 78 imp φx0Fifx0Px+NPx+N-N=Px
80 79 mpteq2dva φx0Fifx0Px+NPx+N-N=x0FPx
81 80 adantl J=N1φx0Fifx0Px+NPx+N-N=x0FPx
82 9 oveq2i NK=NJ+1
83 15 oveq2d J=N1NJ+1=NN-1+1
84 21 oveq2d φNN-1+1=NN
85 55 subidd φNN=0
86 84 85 eqtrd φNN-1+1=0
87 83 86 sylan9eq J=N1φNJ+1=0
88 82 87 eqtrid J=N1φNK=0
89 88 breq2d J=N1φxNKx0
90 9 oveq2i x+K=x+J+1
91 90 fveq2i Px+K=Px+J+1
92 15 oveq2d J=N1x+J+1=x+N1+1
93 21 oveq2d φx+N1+1=x+N
94 92 93 sylan9eq J=N1φx+J+1=x+N
95 94 fveq2d J=N1φPx+J+1=Px+N
96 91 95 eqtrid J=N1φPx+K=Px+N
97 90 oveq1i x+K-N=x+J+1-N
98 97 fveq2i Px+K-N=Px+J+1-N
99 92 oveq1d J=N1x+J+1-N=x+N-1+1-N
100 93 oveq1d φx+N-1+1-N=x+N-N
101 99 100 sylan9eq J=N1φx+J+1-N=x+N-N
102 101 fveq2d J=N1φPx+J+1-N=Px+N-N
103 98 102 eqtrid J=N1φPx+K-N=Px+N-N
104 89 96 103 ifbieq12d J=N1φifxNKPx+KPx+K-N=ifx0Px+NPx+N-N
105 104 mpteq2dv J=N1φx0FifxNKPx+KPx+K-N=x0Fifx0Px+NPx+N-N
106 4 25 syl φFWalksGP
107 1 wlkp FWalksGPP:0FV
108 ffn P:0FVPFn0F
109 106 107 108 3syl φPFn0F
110 109 adantl J=N1φPFn0F
111 dffn5 PFn0FP=x0FPx
112 110 111 sylib J=N1φP=x0FPx
113 81 105 112 3eqtr4d J=N1φx0FifxNKPx+KPx+K-N=P
114 12 34 113 3brtr4d J=N1φFcyclShiftKEulerPathsGx0FifxNKPx+KPx+K-N
115 4 adantl J=N1φFCircuitsGP
116 115 34 113 3brtr4d J=N1φFcyclShiftKCircuitsGx0FifxNKPx+KPx+K-N
117 elfzolt3 J0..^N0<N
118 7 117 syl φ0<N
119 elfzoelz J0..^NJ
120 7 119 syl φJ
121 120 peano2zd φJ+1
122 9 121 eqeltrid φK
123 cshwlen FWorddomIKFcyclShiftK=F
124 123 eqcomd FWorddomIKF=FcyclShiftK
125 28 122 124 syl2anc φF=FcyclShiftK
126 6 125 eqtrd φN=FcyclShiftK
127 118 126 breqtrd φ0<FcyclShiftK
128 127 adantl J=N1φ0<FcyclShiftK
129 126 adantl J=N1φN=FcyclShiftK
130 129 oveq1d J=N1φN1=FcyclShiftK1
131 8 adantl J=N1φiEdgS=IF0..^NJ
132 28 6 7 3jca φFWorddomIN=FJ0..^N
133 132 adantl J=N1φFWorddomIN=FJ0..^N
134 cshimadifsn0 FWorddomIN=FJ0..^NF0..^NJ=FcyclShiftJ+10..^N1
135 133 134 syl J=N1φF0..^NJ=FcyclShiftJ+10..^N1
136 14 imaeq1i FcyclShiftJ+10..^N1=FcyclShiftK0..^N1
137 135 136 eqtrdi J=N1φF0..^NJ=FcyclShiftK0..^N1
138 137 reseq2d J=N1φIF0..^NJ=IFcyclShiftK0..^N1
139 131 138 eqtrd J=N1φiEdgS=IFcyclShiftK0..^N1
140 eqid FcyclShiftKprefixN1=FcyclShiftKprefixN1
141 eqid x0FifxNKPx+KPx+K-N0N1=x0FifxNKPx+KPx+K-N0N1
142 1 2 114 116 5 128 130 139 140 141 eucrct2eupth1 J=N1φFcyclShiftKprefixN1EulerPathsSx0FifxNKPx+KPx+K-N0N1
143 10 a1i J=N1φH=FcyclShiftKprefixN1
144 fzossfz 0..^N0N
145 6 oveq2d φ0N=0F
146 144 145 sseqtrid φ0..^N0F
147 146 resmptd φx0FifxNKPx+KPx+K-N0..^N=x0..^NifxNKPx+KPx+K-N
148 elfzoel2 J0..^NN
149 fzoval N0..^N=0N1
150 7 148 149 3syl φ0..^N=0N1
151 150 reseq2d φx0FifxNKPx+KPx+K-N0..^N=x0FifxNKPx+KPx+K-N0N1
152 147 151 eqtr3d φx0..^NifxNKPx+KPx+K-N=x0FifxNKPx+KPx+K-N0N1
153 11 152 eqtrid φQ=x0FifxNKPx+KPx+K-N0N1
154 153 adantl J=N1φQ=x0FifxNKPx+KPx+K-N0N1
155 142 143 154 3brtr4d J=N1φHEulerPathsSQ
156 4 adantl ¬J=N1φFCircuitsGP
157 peano2nn0 J0J+10
158 157 3ad2ant1 J0NJ<NJ+10
159 158 adantr J0NJ<N¬J=N1J+10
160 simpl2 J0NJ<N¬J=N1N
161 1cnd J0NJ<N1
162 nn0cn J0J
163 162 3ad2ant1 J0NJ<NJ
164 18 161 163 subadd2d J0NJ<NN1=JJ+1=N
165 eqcom J=N1N1=J
166 eqcom N=J+1J+1=N
167 164 165 166 3bitr4g J0NJ<NJ=N1N=J+1
168 167 necon3bbid J0NJ<N¬J=N1NJ+1
169 157 nn0red J0J+1
170 169 3ad2ant1 J0NJ<NJ+1
171 nnre NN
172 171 3ad2ant2 J0NJ<NN
173 nn0z J0J
174 nnz NN
175 zltp1le JNJ<NJ+1N
176 173 174 175 syl2an J0NJ<NJ+1N
177 176 biimp3a J0NJ<NJ+1N
178 170 172 177 leltned J0NJ<NJ+1<NNJ+1
179 178 biimprd J0NJ<NNJ+1J+1<N
180 168 179 sylbid J0NJ<N¬J=N1J+1<N
181 180 imp J0NJ<N¬J=N1J+1<N
182 159 160 181 3jca J0NJ<N¬J=N1J+10NJ+1<N
183 182 ex J0NJ<N¬J=N1J+10NJ+1<N
184 16 183 sylbi J0..^N¬J=N1J+10NJ+1<N
185 elfzo0 J+10..^NJ+10NJ+1<N
186 184 185 syl6ibr J0..^N¬J=N1J+10..^N
187 7 186 syl φ¬J=N1J+10..^N
188 187 impcom ¬J=N1φJ+10..^N
189 9 a1i ¬J=N1φK=J+1
190 6 eqcomd φF=N
191 190 oveq2d φ0..^F=0..^N
192 191 adantl ¬J=N1φ0..^F=0..^N
193 188 189 192 3eltr4d ¬J=N1φK0..^F
194 eqid FcyclShiftK=FcyclShiftK
195 eqid x0FifxFKPx+KPx+K-F=x0FifxFKPx+KPx+K-F
196 3 adantl ¬J=N1φFEulerPathsGP
197 1 2 156 35 193 194 195 196 eucrctshift ¬J=N1φFcyclShiftKEulerPathsGx0FifxFKPx+KPx+K-FFcyclShiftKCircuitsGx0FifxFKPx+KPx+K-F
198 simprl ¬J=N1φFcyclShiftKEulerPathsGx0FifxFKPx+KPx+K-FFcyclShiftKCircuitsGx0FifxFKPx+KPx+K-FFcyclShiftKEulerPathsGx0FifxFKPx+KPx+K-F
199 simprr ¬J=N1φFcyclShiftKEulerPathsGx0FifxFKPx+KPx+K-FFcyclShiftKCircuitsGx0FifxFKPx+KPx+K-FFcyclShiftKCircuitsGx0FifxFKPx+KPx+K-F
200 127 ad2antlr ¬J=N1φFcyclShiftKEulerPathsGx0FifxFKPx+KPx+K-FFcyclShiftKCircuitsGx0FifxFKPx+KPx+K-F0<FcyclShiftK
201 126 oveq1d φN1=FcyclShiftK1
202 201 ad2antlr ¬J=N1φFcyclShiftKEulerPathsGx0FifxFKPx+KPx+K-FFcyclShiftKCircuitsGx0FifxFKPx+KPx+K-FN1=FcyclShiftK1
203 8 adantl ¬J=N1φiEdgS=IF0..^NJ
204 132 adantl ¬J=N1φFWorddomIN=FJ0..^N
205 204 134 syl ¬J=N1φF0..^NJ=FcyclShiftJ+10..^N1
206 205 136 eqtrdi ¬J=N1φF0..^NJ=FcyclShiftK0..^N1
207 206 reseq2d ¬J=N1φIF0..^NJ=IFcyclShiftK0..^N1
208 203 207 eqtrd ¬J=N1φiEdgS=IFcyclShiftK0..^N1
209 208 adantr ¬J=N1φFcyclShiftKEulerPathsGx0FifxFKPx+KPx+K-FFcyclShiftKCircuitsGx0FifxFKPx+KPx+K-FiEdgS=IFcyclShiftK0..^N1
210 eqid x0FifxFKPx+KPx+K-F0N1=x0FifxFKPx+KPx+K-F0N1
211 1 2 198 199 5 200 202 209 140 210 eucrct2eupth1 ¬J=N1φFcyclShiftKEulerPathsGx0FifxFKPx+KPx+K-FFcyclShiftKCircuitsGx0FifxFKPx+KPx+K-FFcyclShiftKprefixN1EulerPathsSx0FifxFKPx+KPx+K-F0N1
212 10 a1i ¬J=N1φFcyclShiftKEulerPathsGx0FifxFKPx+KPx+K-FFcyclShiftKCircuitsGx0FifxFKPx+KPx+K-FH=FcyclShiftKprefixN1
213 190 oveq1d φFK=NK
214 213 breq2d φxFKxNK
215 214 adantl ¬J=N1φxFKxNK
216 190 oveq2d φx+K-F=x+K-N
217 216 fveq2d φPx+K-F=Px+K-N
218 217 adantl ¬J=N1φPx+K-F=Px+K-N
219 215 218 ifbieq2d ¬J=N1φifxFKPx+KPx+K-F=ifxNKPx+KPx+K-N
220 219 mpteq2dv ¬J=N1φx0FifxFKPx+KPx+K-F=x0FifxNKPx+KPx+K-N
221 150 eqcomd φ0N1=0..^N
222 221 adantl ¬J=N1φ0N1=0..^N
223 220 222 reseq12d ¬J=N1φx0FifxFKPx+KPx+K-F0N1=x0FifxNKPx+KPx+K-N0..^N
224 6 adantl ¬J=N1φN=F
225 224 oveq2d ¬J=N1φ0N=0F
226 144 225 sseqtrid ¬J=N1φ0..^N0F
227 226 resmptd ¬J=N1φx0FifxNKPx+KPx+K-N0..^N=x0..^NifxNKPx+KPx+K-N
228 223 227 eqtrd ¬J=N1φx0FifxFKPx+KPx+K-F0N1=x0..^NifxNKPx+KPx+K-N
229 11 228 eqtr4id ¬J=N1φQ=x0FifxFKPx+KPx+K-F0N1
230 229 adantr ¬J=N1φFcyclShiftKEulerPathsGx0FifxFKPx+KPx+K-FFcyclShiftKCircuitsGx0FifxFKPx+KPx+K-FQ=x0FifxFKPx+KPx+K-F0N1
231 211 212 230 3brtr4d ¬J=N1φFcyclShiftKEulerPathsGx0FifxFKPx+KPx+K-FFcyclShiftKCircuitsGx0FifxFKPx+KPx+K-FHEulerPathsSQ
232 197 231 mpdan ¬J=N1φHEulerPathsSQ
233 155 232 pm2.61ian φHEulerPathsSQ