Metamath Proof Explorer


Theorem cycldlenngric

Description: Two simple pseudographs are not isomorphic if one has a cycle and the other has no cycle of the same length. (Contributed by AV, 6-Nov-2025)

Ref Expression
Assertion cycldlenngric ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) → ( ( ∃ 𝑝𝑓 ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ∧ ¬ ∃ 𝑝𝑓 ( 𝑓 ( Cycles ‘ 𝐻 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) → ¬ 𝐺𝑔𝑟 𝐻 ) )

Proof

Step Hyp Ref Expression
1 brgric ( 𝐺𝑔𝑟 𝐻 ↔ ( 𝐺 GraphIso 𝐻 ) ≠ ∅ )
2 n0rex ( ( 𝐺 GraphIso 𝐻 ) ≠ ∅ → ∃ 𝑖 ∈ ( 𝐺 GraphIso 𝐻 ) 𝑖 ∈ ( 𝐺 GraphIso 𝐻 ) )
3 eqid ( iEdg ‘ 𝐺 ) = ( iEdg ‘ 𝐺 )
4 eqid ( iEdg ‘ 𝐻 ) = ( iEdg ‘ 𝐻 )
5 simprll ( ( 𝑖 ∈ ( 𝐺 GraphIso 𝐻 ) ∧ ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) ) → 𝐺 ∈ USPGraph )
6 simprlr ( ( 𝑖 ∈ ( 𝐺 GraphIso 𝐻 ) ∧ ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) ) → 𝐻 ∈ USPGraph )
7 simpl ( ( 𝑖 ∈ ( 𝐺 GraphIso 𝐻 ) ∧ ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) ) → 𝑖 ∈ ( 𝐺 GraphIso 𝐻 ) )
8 2fveq3 ( 𝑥 = 𝑗 → ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) = ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑗 ) ) )
9 8 imaeq2d ( 𝑥 = 𝑗 → ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) = ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑗 ) ) ) )
10 9 fveq2d ( 𝑥 = 𝑗 → ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) = ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑗 ) ) ) ) )
11 10 cbvmptv ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) = ( 𝑗 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑗 ) ) ) ) )
12 cycliswlk ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝𝑓 ( Walks ‘ 𝐺 ) 𝑝 )
13 12 ad2antrl ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) → 𝑓 ( Walks ‘ 𝐺 ) 𝑝 )
14 13 adantl ( ( 𝑖 ∈ ( 𝐺 GraphIso 𝐻 ) ∧ ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) ) → 𝑓 ( Walks ‘ 𝐺 ) 𝑝 )
15 3 4 5 6 7 11 14 upgrimwlklen ( ( 𝑖 ∈ ( 𝐺 GraphIso 𝐻 ) ∧ ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) ) → ( ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ( Walks ‘ 𝐻 ) ( 𝑖𝑝 ) ∧ ( ♯ ‘ ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ) = ( ♯ ‘ 𝑓 ) ) )
16 simprrl ( ( 𝑖 ∈ ( 𝐺 GraphIso 𝐻 ) ∧ ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) ) → 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 )
17 3 4 5 6 7 11 16 upgrimcycls ( ( 𝑖 ∈ ( 𝐺 GraphIso 𝐻 ) ∧ ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) ) → ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ( Cycles ‘ 𝐻 ) ( 𝑖𝑝 ) )
18 simp3 ( ( ( 𝑖 ∈ ( 𝐺 GraphIso 𝐻 ) ∧ ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) ) ∧ ( ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ( Walks ‘ 𝐻 ) ( 𝑖𝑝 ) ∧ ( ♯ ‘ ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ) = ( ♯ ‘ 𝑓 ) ) ∧ ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ( Cycles ‘ 𝐻 ) ( 𝑖𝑝 ) ) → ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ( Cycles ‘ 𝐻 ) ( 𝑖𝑝 ) )
19 simp2r ( ( ( 𝑖 ∈ ( 𝐺 GraphIso 𝐻 ) ∧ ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) ) ∧ ( ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ( Walks ‘ 𝐻 ) ( 𝑖𝑝 ) ∧ ( ♯ ‘ ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ) = ( ♯ ‘ 𝑓 ) ) ∧ ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ( Cycles ‘ 𝐻 ) ( 𝑖𝑝 ) ) → ( ♯ ‘ ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ) = ( ♯ ‘ 𝑓 ) )
20 simprrr ( ( 𝑖 ∈ ( 𝐺 GraphIso 𝐻 ) ∧ ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) ) → ( ♯ ‘ 𝑓 ) = 𝑁 )
21 20 3ad2ant1 ( ( ( 𝑖 ∈ ( 𝐺 GraphIso 𝐻 ) ∧ ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) ) ∧ ( ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ( Walks ‘ 𝐻 ) ( 𝑖𝑝 ) ∧ ( ♯ ‘ ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ) = ( ♯ ‘ 𝑓 ) ) ∧ ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ( Cycles ‘ 𝐻 ) ( 𝑖𝑝 ) ) → ( ♯ ‘ 𝑓 ) = 𝑁 )
22 19 21 eqtrd ( ( ( 𝑖 ∈ ( 𝐺 GraphIso 𝐻 ) ∧ ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) ) ∧ ( ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ( Walks ‘ 𝐻 ) ( 𝑖𝑝 ) ∧ ( ♯ ‘ ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ) = ( ♯ ‘ 𝑓 ) ) ∧ ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ( Cycles ‘ 𝐻 ) ( 𝑖𝑝 ) ) → ( ♯ ‘ ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ) = 𝑁 )
23 vex 𝑖 ∈ V
24 vex 𝑝 ∈ V
25 23 24 coex ( 𝑖𝑝 ) ∈ V
26 vex 𝑓 ∈ V
27 26 dmex dom 𝑓 ∈ V
28 27 mptex ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ∈ V
29 breq12 ( ( 𝑔 = ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ∧ 𝑞 = ( 𝑖𝑝 ) ) → ( 𝑔 ( Cycles ‘ 𝐻 ) 𝑞 ↔ ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ( Cycles ‘ 𝐻 ) ( 𝑖𝑝 ) ) )
30 29 ancoms ( ( 𝑞 = ( 𝑖𝑝 ) ∧ 𝑔 = ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ) → ( 𝑔 ( Cycles ‘ 𝐻 ) 𝑞 ↔ ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ( Cycles ‘ 𝐻 ) ( 𝑖𝑝 ) ) )
31 fveqeq2 ( 𝑔 = ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) → ( ( ♯ ‘ 𝑔 ) = 𝑁 ↔ ( ♯ ‘ ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ) = 𝑁 ) )
32 31 adantl ( ( 𝑞 = ( 𝑖𝑝 ) ∧ 𝑔 = ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ) → ( ( ♯ ‘ 𝑔 ) = 𝑁 ↔ ( ♯ ‘ ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ) = 𝑁 ) )
33 30 32 anbi12d ( ( 𝑞 = ( 𝑖𝑝 ) ∧ 𝑔 = ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ) → ( ( 𝑔 ( Cycles ‘ 𝐻 ) 𝑞 ∧ ( ♯ ‘ 𝑔 ) = 𝑁 ) ↔ ( ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ( Cycles ‘ 𝐻 ) ( 𝑖𝑝 ) ∧ ( ♯ ‘ ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ) = 𝑁 ) ) )
34 25 28 33 spc2ev ( ( ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ( Cycles ‘ 𝐻 ) ( 𝑖𝑝 ) ∧ ( ♯ ‘ ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ) = 𝑁 ) → ∃ 𝑞𝑔 ( 𝑔 ( Cycles ‘ 𝐻 ) 𝑞 ∧ ( ♯ ‘ 𝑔 ) = 𝑁 ) )
35 18 22 34 syl2anc ( ( ( 𝑖 ∈ ( 𝐺 GraphIso 𝐻 ) ∧ ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) ) ∧ ( ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ( Walks ‘ 𝐻 ) ( 𝑖𝑝 ) ∧ ( ♯ ‘ ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ) = ( ♯ ‘ 𝑓 ) ) ∧ ( 𝑥 ∈ dom 𝑓 ↦ ( ( iEdg ‘ 𝐻 ) ‘ ( 𝑖 “ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝑓𝑥 ) ) ) ) ) ( Cycles ‘ 𝐻 ) ( 𝑖𝑝 ) ) → ∃ 𝑞𝑔 ( 𝑔 ( Cycles ‘ 𝐻 ) 𝑞 ∧ ( ♯ ‘ 𝑔 ) = 𝑁 ) )
36 15 17 35 mpd3an23 ( ( 𝑖 ∈ ( 𝐺 GraphIso 𝐻 ) ∧ ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) ) → ∃ 𝑞𝑔 ( 𝑔 ( Cycles ‘ 𝐻 ) 𝑞 ∧ ( ♯ ‘ 𝑔 ) = 𝑁 ) )
37 36 ex ( 𝑖 ∈ ( 𝐺 GraphIso 𝐻 ) → ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) → ∃ 𝑞𝑔 ( 𝑔 ( Cycles ‘ 𝐻 ) 𝑞 ∧ ( ♯ ‘ 𝑔 ) = 𝑁 ) ) )
38 37 rexlimivw ( ∃ 𝑖 ∈ ( 𝐺 GraphIso 𝐻 ) 𝑖 ∈ ( 𝐺 GraphIso 𝐻 ) → ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) → ∃ 𝑞𝑔 ( 𝑔 ( Cycles ‘ 𝐻 ) 𝑞 ∧ ( ♯ ‘ 𝑔 ) = 𝑁 ) ) )
39 2 38 syl ( ( 𝐺 GraphIso 𝐻 ) ≠ ∅ → ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) → ∃ 𝑞𝑔 ( 𝑔 ( Cycles ‘ 𝐻 ) 𝑞 ∧ ( ♯ ‘ 𝑔 ) = 𝑁 ) ) )
40 1 39 sylbi ( 𝐺𝑔𝑟 𝐻 → ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) → ∃ 𝑞𝑔 ( 𝑔 ( Cycles ‘ 𝐻 ) 𝑞 ∧ ( ♯ ‘ 𝑔 ) = 𝑁 ) ) )
41 40 expdcom ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) → ( ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) → ( 𝐺𝑔𝑟 𝐻 → ∃ 𝑞𝑔 ( 𝑔 ( Cycles ‘ 𝐻 ) 𝑞 ∧ ( ♯ ‘ 𝑔 ) = 𝑁 ) ) ) )
42 41 exlimdvv ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) → ( ∃ 𝑝𝑓 ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) → ( 𝐺𝑔𝑟 𝐻 → ∃ 𝑞𝑔 ( 𝑔 ( Cycles ‘ 𝐻 ) 𝑞 ∧ ( ♯ ‘ 𝑔 ) = 𝑁 ) ) ) )
43 42 imp ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ∃ 𝑝𝑓 ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) → ( 𝐺𝑔𝑟 𝐻 → ∃ 𝑞𝑔 ( 𝑔 ( Cycles ‘ 𝐻 ) 𝑞 ∧ ( ♯ ‘ 𝑔 ) = 𝑁 ) ) )
44 breq12 ( ( 𝑓 = 𝑔𝑝 = 𝑞 ) → ( 𝑓 ( Cycles ‘ 𝐻 ) 𝑝𝑔 ( Cycles ‘ 𝐻 ) 𝑞 ) )
45 44 ancoms ( ( 𝑝 = 𝑞𝑓 = 𝑔 ) → ( 𝑓 ( Cycles ‘ 𝐻 ) 𝑝𝑔 ( Cycles ‘ 𝐻 ) 𝑞 ) )
46 fveqeq2 ( 𝑓 = 𝑔 → ( ( ♯ ‘ 𝑓 ) = 𝑁 ↔ ( ♯ ‘ 𝑔 ) = 𝑁 ) )
47 46 adantl ( ( 𝑝 = 𝑞𝑓 = 𝑔 ) → ( ( ♯ ‘ 𝑓 ) = 𝑁 ↔ ( ♯ ‘ 𝑔 ) = 𝑁 ) )
48 45 47 anbi12d ( ( 𝑝 = 𝑞𝑓 = 𝑔 ) → ( ( 𝑓 ( Cycles ‘ 𝐻 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ↔ ( 𝑔 ( Cycles ‘ 𝐻 ) 𝑞 ∧ ( ♯ ‘ 𝑔 ) = 𝑁 ) ) )
49 48 cbvex2vw ( ∃ 𝑝𝑓 ( 𝑓 ( Cycles ‘ 𝐻 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ↔ ∃ 𝑞𝑔 ( 𝑔 ( Cycles ‘ 𝐻 ) 𝑞 ∧ ( ♯ ‘ 𝑔 ) = 𝑁 ) )
50 43 49 imbitrrdi ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ∃ 𝑝𝑓 ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) → ( 𝐺𝑔𝑟 𝐻 → ∃ 𝑝𝑓 ( 𝑓 ( Cycles ‘ 𝐻 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) )
51 50 con3d ( ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) ∧ ∃ 𝑝𝑓 ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) → ( ¬ ∃ 𝑝𝑓 ( 𝑓 ( Cycles ‘ 𝐻 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) → ¬ 𝐺𝑔𝑟 𝐻 ) )
52 51 expimpd ( ( 𝐺 ∈ USPGraph ∧ 𝐻 ∈ USPGraph ) → ( ( ∃ 𝑝𝑓 ( 𝑓 ( Cycles ‘ 𝐺 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ∧ ¬ ∃ 𝑝𝑓 ( 𝑓 ( Cycles ‘ 𝐻 ) 𝑝 ∧ ( ♯ ‘ 𝑓 ) = 𝑁 ) ) → ¬ 𝐺𝑔𝑟 𝐻 ) )