Theorem isrusgr 26457

Description: The property of being a k-regular simple graph. (Contributed by Alexander van der Vekens, 7-Jul-2018.) (Revised by AV, 18-Dec-2020.)

Assertion

Ref	Expression
isrusgr	|- ( ( G e. W /\ K e. Z ) -> ( G RegUSGraph K <-> ( G e. USGraph /\ G RegGraph K ) ) )

Proof of Theorem isrusgr

Dummy variables g k are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		eleq1 2689	. . . . 5 |- ( g = G -> ( g e. USGraph <-> G e. USGraph ) )
2	1	adantr 481	. . . 4 |- ( ( g = G /\ k = K ) -> ( g e. USGraph <-> G e. USGraph ) )
3		breq12 4658	. . . 4 |- ( ( g = G /\ k = K ) -> ( g RegGraph k <-> G RegGraph K ) )
4	2, 3	anbi12d 747	. . 3 |- ( ( g = G /\ k = K ) -> ( ( g e. USGraph /\ g RegGraph k ) <-> ( G e. USGraph /\ G RegGraph K ) ) )
5		df-rusgr 26454	. . 3 |- RegUSGraph = { <. g , k >. | ( g e. USGraph /\ g RegGraph k ) }
6	4, 5	brabga 4989	. 2 |- ( ( G e. W /\ K e. Z ) -> ( G RegUSGraph K <-> ( G e. USGraph /\ G RegGraph K ) ) )
7		biidd 252	. 2 |- ( ( G e. W /\ K e. Z ) -> ( ( G e. USGraph /\ G RegGraph K ) <-> ( G e. USGraph /\ G RegGraph K ) ) )
8	6, 7	bitrd 268	1 |- ( ( G e. W /\ K e. Z ) -> ( G RegUSGraph K <-> ( G e. USGraph /\ G RegGraph K ) ) )

Syntax hints:   -> wi 4   <-> wb 196   /\ wa 384   = wceq 1483   e. wcel 1990   class class class wbr 4653   USGraph cusgr 26044   RegGraph crgr 26451   RegUSGraph crusgr 26452

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1722  ax-4 1737  ax-5 1839  ax-6 1888  ax-7 1935  ax-9 1999  ax-10 2019  ax-11 2034  ax-12 2047  ax-13 2246  ax-ext 2602  ax-sep 4781  ax-nul 4789  ax-pr 4906

This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-3an 1039  df-tru 1486  df-ex 1705  df-nf 1710  df-sb 1881  df-eu 2474  df-mo 2475  df-clab 2609  df-cleq 2615  df-clel 2618  df-nfc 2753  df-rab 2921  df-v 3202  df-dif 3577  df-un 3579  df-in 3581  df-ss 3588  df-nul 3916  df-if 4087  df-sn 4178  df-pr 4180  df-op 4184  df-br 4654  df-opab 4713  df-rusgr 26454

This theorem is referenced by:  rusgrprop  26458  isrusgr0  26462  usgr0edg0rusgr  26471  0vtxrusgr  26473