Theorem istrl 28953

Description: Conditions for a pair of classes/functions to be a trail (in an undirected graph). (Contributed by Alexander van der Vekens, 20-Oct-2017.) (Revised by AV, 28-Dec-2020.) (Revised by AV, 29-Oct-2021.)

Assertion

Ref	Expression
istrl	⊢ (𝐹(Trails‘𝐺)𝑃 ↔ (𝐹(Walks‘𝐺)𝑃 ∧ Fun ◡𝐹))

Proof of Theorem istrl

Dummy variables 𝑓 𝑝 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		trlsfval 28952	. 2 ⊢ (Trails‘𝐺) = {⟨𝑓, 𝑝⟩ ∣ (𝑓(Walks‘𝐺)𝑝 ∧ Fun ◡𝑓)}
2		cnveq 5874	. . . 4 ⊢ (𝑓 = 𝐹 → ◡𝑓 = ◡𝐹)
3	2	funeqd 6571	. . 3 ⊢ (𝑓 = 𝐹 → (Fun ◡𝑓 ↔ Fun ◡𝐹))
4	3	adantr 482	. 2 ⊢ ((𝑓 = 𝐹 ∧ 𝑝 = 𝑃) → (Fun ◡𝑓 ↔ Fun ◡𝐹))
5		relwlk 28883	. 2 ⊢ Rel (Walks‘𝐺)
6	1, 4, 5	brfvopabrbr 6996	1 ⊢ (𝐹(Trails‘𝐺)𝑃 ↔ (𝐹(Walks‘𝐺)𝑃 ∧ Fun ◡𝐹))

Syntax hints:   ↔ wb 205   ∧ wa 397   = wceq 1542   class class class wbr 5149  ^◡ccnv 5676  Fun wfun 6538  ‘cfv 6544  Walkscwlks 28853  Trailsctrls 28947

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1798  ax-4 1812  ax-5 1914  ax-6 1972  ax-7 2012  ax-8 2109  ax-9 2117  ax-10 2138  ax-11 2155  ax-12 2172  ax-ext 2704  ax-sep 5300  ax-nul 5307  ax-pr 5428

This theorem depends on definitions:  df-bi 206  df-an 398  df-or 847  df-3an 1090  df-tru 1545  df-fal 1555  df-ex 1783  df-nf 1787  df-sb 2069  df-mo 2535  df-eu 2564  df-clab 2711  df-cleq 2725  df-clel 2811  df-nfc 2886  df-ne 2942  df-ral 3063  df-rex 3072  df-rab 3434  df-v 3477  df-sbc 3779  df-csb 3895  df-dif 3952  df-un 3954  df-in 3956  df-ss 3966  df-nul 4324  df-if 4530  df-sn 4630  df-pr 4632  df-op 4636  df-uni 4910  df-br 5150  df-opab 5212  df-mpt 5233  df-id 5575  df-xp 5683  df-rel 5684  df-cnv 5685  df-co 5686  df-dm 5687  df-rn 5688  df-res 5689  df-ima 5690  df-iota 6496  df-fun 6546  df-fv 6552  df-wlks 28856  df-trls 28949

This theorem is referenced by:  trliswlk  28954  trlf1  28955  trlres  28957  upgristrl  28959  2pthnloop  28988  upgrspthswlk  28995  uhgrwkspth  29012  usgr2wlkspth  29016  uspgrn2crct  29062  crctcshtrl  29077  2trld  29192  0trl  29375  1trld  29395  ntrl2v2e  29411  3trld  29425  iseupthf1o  29455  subgrtrl  34124