Metamath Proof Explorer


Theorem grlimprclnbgredg

Description: For two locally isomorphic graphs G and H and a vertex A of G there is a bijection f mapping the closed neighborhood N of A onto the closed neighborhood M of ( FA ) , so that the mapped vertices of an edge { A , B } containing the vertex A is an edge between the vertices in M . (Contributed by AV, 27-Dec-2025)

Ref Expression
Hypotheses clnbgrvtxedg.n 𝑁 = ( 𝐺 ClNeighbVtx 𝐴 )
clnbgrvtxedg.i 𝐼 = ( Edg ‘ 𝐺 )
clnbgrvtxedg.k 𝐾 = { 𝑥𝐼𝑥𝑁 }
grlimedgclnbgr.m 𝑀 = ( 𝐻 ClNeighbVtx ( 𝐹𝐴 ) )
grlimedgclnbgr.j 𝐽 = ( Edg ‘ 𝐻 )
grlimedgclnbgr.l 𝐿 = { 𝑥𝐽𝑥𝑀 }
Assertion grlimprclnbgredg ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ 𝐹 ∈ ( 𝐺 GraphLocIso 𝐻 ) ∧ ( 𝐴𝑉𝐵𝑊 ∧ { 𝐴 , 𝐵 } ∈ 𝐼 ) ) → ∃ 𝑓 ( 𝑓 : 𝑁1-1-onto𝑀 ∧ { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } ∈ 𝐿 ) )

Proof

Step Hyp Ref Expression
1 clnbgrvtxedg.n 𝑁 = ( 𝐺 ClNeighbVtx 𝐴 )
2 clnbgrvtxedg.i 𝐼 = ( Edg ‘ 𝐺 )
3 clnbgrvtxedg.k 𝐾 = { 𝑥𝐼𝑥𝑁 }
4 grlimedgclnbgr.m 𝑀 = ( 𝐻 ClNeighbVtx ( 𝐹𝐴 ) )
5 grlimedgclnbgr.j 𝐽 = ( Edg ‘ 𝐻 )
6 grlimedgclnbgr.l 𝐿 = { 𝑥𝐽𝑥𝑀 }
7 1 2 3 4 5 6 grlimprclnbgr ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ 𝐹 ∈ ( 𝐺 GraphLocIso 𝐻 ) ∧ ( 𝐴𝑉𝐵𝑊 ∧ { 𝐴 , 𝐵 } ∈ 𝐼 ) ) → ∃ 𝑓𝑔 ( 𝑓 : 𝑁1-1-onto𝑀𝑔 : 𝐾1-1-onto𝐿 ∧ { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } = ( 𝑔 ‘ { 𝐴 , 𝐵 } ) ) )
8 simpr1 ( ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ 𝐹 ∈ ( 𝐺 GraphLocIso 𝐻 ) ∧ ( 𝐴𝑉𝐵𝑊 ∧ { 𝐴 , 𝐵 } ∈ 𝐼 ) ) ∧ ( 𝑓 : 𝑁1-1-onto𝑀𝑔 : 𝐾1-1-onto𝐿 ∧ { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } = ( 𝑔 ‘ { 𝐴 , 𝐵 } ) ) ) → 𝑓 : 𝑁1-1-onto𝑀 )
9 f1of ( 𝑔 : 𝐾1-1-onto𝐿𝑔 : 𝐾𝐿 )
10 9 3ad2ant2 ( ( 𝑓 : 𝑁1-1-onto𝑀𝑔 : 𝐾1-1-onto𝐿 ∧ { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } = ( 𝑔 ‘ { 𝐴 , 𝐵 } ) ) → 𝑔 : 𝐾𝐿 )
11 10 adantl ( ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ 𝐹 ∈ ( 𝐺 GraphLocIso 𝐻 ) ∧ ( 𝐴𝑉𝐵𝑊 ∧ { 𝐴 , 𝐵 } ∈ 𝐼 ) ) ∧ ( 𝑓 : 𝑁1-1-onto𝑀𝑔 : 𝐾1-1-onto𝐿 ∧ { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } = ( 𝑔 ‘ { 𝐴 , 𝐵 } ) ) ) → 𝑔 : 𝐾𝐿 )
12 uspgruhgr ( 𝐺 ∈ USPGraph → 𝐺 ∈ UHGraph )
13 12 adantr ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) → 𝐺 ∈ UHGraph )
14 13 3ad2ant1 ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ 𝐹 ∈ ( 𝐺 GraphLocIso 𝐻 ) ∧ ( 𝐴𝑉𝐵𝑊 ∧ { 𝐴 , 𝐵 } ∈ 𝐼 ) ) → 𝐺 ∈ UHGraph )
15 simp33 ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ 𝐹 ∈ ( 𝐺 GraphLocIso 𝐻 ) ∧ ( 𝐴𝑉𝐵𝑊 ∧ { 𝐴 , 𝐵 } ∈ 𝐼 ) ) → { 𝐴 , 𝐵 } ∈ 𝐼 )
16 prid1g ( 𝐴𝑉𝐴 ∈ { 𝐴 , 𝐵 } )
17 16 3ad2ant1 ( ( 𝐴𝑉𝐵𝑊 ∧ { 𝐴 , 𝐵 } ∈ 𝐼 ) → 𝐴 ∈ { 𝐴 , 𝐵 } )
18 17 3ad2ant3 ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ 𝐹 ∈ ( 𝐺 GraphLocIso 𝐻 ) ∧ ( 𝐴𝑉𝐵𝑊 ∧ { 𝐴 , 𝐵 } ∈ 𝐼 ) ) → 𝐴 ∈ { 𝐴 , 𝐵 } )
19 14 15 18 3jca ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ 𝐹 ∈ ( 𝐺 GraphLocIso 𝐻 ) ∧ ( 𝐴𝑉𝐵𝑊 ∧ { 𝐴 , 𝐵 } ∈ 𝐼 ) ) → ( 𝐺 ∈ UHGraph ∧ { 𝐴 , 𝐵 } ∈ 𝐼𝐴 ∈ { 𝐴 , 𝐵 } ) )
20 19 adantr ( ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ 𝐹 ∈ ( 𝐺 GraphLocIso 𝐻 ) ∧ ( 𝐴𝑉𝐵𝑊 ∧ { 𝐴 , 𝐵 } ∈ 𝐼 ) ) ∧ ( 𝑓 : 𝑁1-1-onto𝑀𝑔 : 𝐾1-1-onto𝐿 ∧ { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } = ( 𝑔 ‘ { 𝐴 , 𝐵 } ) ) ) → ( 𝐺 ∈ UHGraph ∧ { 𝐴 , 𝐵 } ∈ 𝐼𝐴 ∈ { 𝐴 , 𝐵 } ) )
21 1 2 3 clnbgrvtxedg ( ( 𝐺 ∈ UHGraph ∧ { 𝐴 , 𝐵 } ∈ 𝐼𝐴 ∈ { 𝐴 , 𝐵 } ) → { 𝐴 , 𝐵 } ∈ 𝐾 )
22 20 21 syl ( ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ 𝐹 ∈ ( 𝐺 GraphLocIso 𝐻 ) ∧ ( 𝐴𝑉𝐵𝑊 ∧ { 𝐴 , 𝐵 } ∈ 𝐼 ) ) ∧ ( 𝑓 : 𝑁1-1-onto𝑀𝑔 : 𝐾1-1-onto𝐿 ∧ { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } = ( 𝑔 ‘ { 𝐴 , 𝐵 } ) ) ) → { 𝐴 , 𝐵 } ∈ 𝐾 )
23 11 22 ffvelcdmd ( ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ 𝐹 ∈ ( 𝐺 GraphLocIso 𝐻 ) ∧ ( 𝐴𝑉𝐵𝑊 ∧ { 𝐴 , 𝐵 } ∈ 𝐼 ) ) ∧ ( 𝑓 : 𝑁1-1-onto𝑀𝑔 : 𝐾1-1-onto𝐿 ∧ { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } = ( 𝑔 ‘ { 𝐴 , 𝐵 } ) ) ) → ( 𝑔 ‘ { 𝐴 , 𝐵 } ) ∈ 𝐿 )
24 eleq1 ( { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } = ( 𝑔 ‘ { 𝐴 , 𝐵 } ) → ( { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } ∈ 𝐿 ↔ ( 𝑔 ‘ { 𝐴 , 𝐵 } ) ∈ 𝐿 ) )
25 24 3ad2ant3 ( ( 𝑓 : 𝑁1-1-onto𝑀𝑔 : 𝐾1-1-onto𝐿 ∧ { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } = ( 𝑔 ‘ { 𝐴 , 𝐵 } ) ) → ( { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } ∈ 𝐿 ↔ ( 𝑔 ‘ { 𝐴 , 𝐵 } ) ∈ 𝐿 ) )
26 25 adantl ( ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ 𝐹 ∈ ( 𝐺 GraphLocIso 𝐻 ) ∧ ( 𝐴𝑉𝐵𝑊 ∧ { 𝐴 , 𝐵 } ∈ 𝐼 ) ) ∧ ( 𝑓 : 𝑁1-1-onto𝑀𝑔 : 𝐾1-1-onto𝐿 ∧ { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } = ( 𝑔 ‘ { 𝐴 , 𝐵 } ) ) ) → ( { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } ∈ 𝐿 ↔ ( 𝑔 ‘ { 𝐴 , 𝐵 } ) ∈ 𝐿 ) )
27 23 26 mpbird ( ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ 𝐹 ∈ ( 𝐺 GraphLocIso 𝐻 ) ∧ ( 𝐴𝑉𝐵𝑊 ∧ { 𝐴 , 𝐵 } ∈ 𝐼 ) ) ∧ ( 𝑓 : 𝑁1-1-onto𝑀𝑔 : 𝐾1-1-onto𝐿 ∧ { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } = ( 𝑔 ‘ { 𝐴 , 𝐵 } ) ) ) → { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } ∈ 𝐿 )
28 8 27 jca ( ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ 𝐹 ∈ ( 𝐺 GraphLocIso 𝐻 ) ∧ ( 𝐴𝑉𝐵𝑊 ∧ { 𝐴 , 𝐵 } ∈ 𝐼 ) ) ∧ ( 𝑓 : 𝑁1-1-onto𝑀𝑔 : 𝐾1-1-onto𝐿 ∧ { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } = ( 𝑔 ‘ { 𝐴 , 𝐵 } ) ) ) → ( 𝑓 : 𝑁1-1-onto𝑀 ∧ { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } ∈ 𝐿 ) )
29 28 ex ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ 𝐹 ∈ ( 𝐺 GraphLocIso 𝐻 ) ∧ ( 𝐴𝑉𝐵𝑊 ∧ { 𝐴 , 𝐵 } ∈ 𝐼 ) ) → ( ( 𝑓 : 𝑁1-1-onto𝑀𝑔 : 𝐾1-1-onto𝐿 ∧ { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } = ( 𝑔 ‘ { 𝐴 , 𝐵 } ) ) → ( 𝑓 : 𝑁1-1-onto𝑀 ∧ { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } ∈ 𝐿 ) ) )
30 29 exlimdv ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ 𝐹 ∈ ( 𝐺 GraphLocIso 𝐻 ) ∧ ( 𝐴𝑉𝐵𝑊 ∧ { 𝐴 , 𝐵 } ∈ 𝐼 ) ) → ( ∃ 𝑔 ( 𝑓 : 𝑁1-1-onto𝑀𝑔 : 𝐾1-1-onto𝐿 ∧ { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } = ( 𝑔 ‘ { 𝐴 , 𝐵 } ) ) → ( 𝑓 : 𝑁1-1-onto𝑀 ∧ { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } ∈ 𝐿 ) ) )
31 30 eximdv ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ 𝐹 ∈ ( 𝐺 GraphLocIso 𝐻 ) ∧ ( 𝐴𝑉𝐵𝑊 ∧ { 𝐴 , 𝐵 } ∈ 𝐼 ) ) → ( ∃ 𝑓𝑔 ( 𝑓 : 𝑁1-1-onto𝑀𝑔 : 𝐾1-1-onto𝐿 ∧ { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } = ( 𝑔 ‘ { 𝐴 , 𝐵 } ) ) → ∃ 𝑓 ( 𝑓 : 𝑁1-1-onto𝑀 ∧ { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } ∈ 𝐿 ) ) )
32 7 31 mpd ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ 𝐹 ∈ ( 𝐺 GraphLocIso 𝐻 ) ∧ ( 𝐴𝑉𝐵𝑊 ∧ { 𝐴 , 𝐵 } ∈ 𝐼 ) ) → ∃ 𝑓 ( 𝑓 : 𝑁1-1-onto𝑀 ∧ { ( 𝑓𝐴 ) , ( 𝑓𝐵 ) } ∈ 𝐿 ) )