Theorem vtxdgop 16533

Description: The vertex degree expressed as operation. (Contributed by AV, 12-Dec-2021.)

Assertion

Ref	Expression
vtxdgop	|- ( G e. W -> (VtxDeg ` G ) = ( (Vtx ` G )VtxDeg (iEdg ` G ) ) )

Proof of Theorem vtxdgop

Dummy variables u x are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		vtxex 16259	. . . . 5 |- ( G e. W -> (Vtx ` G ) e. _V )
2		iedgex 16260	. . . . 5 |- ( G e. W -> (iEdg ` G ) e. _V )
3		opexg 4368	. . . . 5 |- ( ( (Vtx ` G ) e. _V /\ (iEdg ` G ) e. _V ) -> <. (Vtx ` G ) , (iEdg ` G ) >. e. _V )
4	1, 2, 3	syl2anc 415	. . . 4 |- ( G e. W -> <. (Vtx ` G ) , (iEdg ` G ) >. e. _V )
5		eqid 2238	. . . . 5 |- (Vtx ` <. (Vtx ` G ) , (iEdg ` G ) >. ) = (Vtx ` <. (Vtx ` G ) , (iEdg ` G ) >. )
6		eqid 2238	. . . . 5 |- (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) = (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. )
7		eqid 2238	. . . . 5 |- dom (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) = dom (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. )
8	5, 6, 7	vtxdgfval 16529	. . . 4 |- ( <. (Vtx ` G ) , (iEdg ` G ) >. e. _V -> (VtxDeg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) = ( u e. (Vtx ` <. (Vtx ` G ) , (iEdg ` G ) >. ) |-> ( (♯ ` { x e. dom (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) | u e. ( (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) ` x ) } ) +e (♯ ` { x e. dom (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) | ( (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) ` x ) = { u } } ) ) ) )
9	4, 8	syl 14	. . 3 |- ( G e. W -> (VtxDeg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) = ( u e. (Vtx ` <. (Vtx ` G ) , (iEdg ` G ) >. ) |-> ( (♯ ` { x e. dom (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) | u e. ( (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) ` x ) } ) +e (♯ ` { x e. dom (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) | ( (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) ` x ) = { u } } ) ) ) )
10		opvtxfv 16263	. . . . 5 |- ( ( (Vtx ` G ) e. _V /\ (iEdg ` G ) e. _V ) -> (Vtx ` <. (Vtx ` G ) , (iEdg ` G ) >. ) = (Vtx ` G ) )
11	1, 2, 10	syl2anc 415	. . . 4 |- ( G e. W -> (Vtx ` <. (Vtx ` G ) , (iEdg ` G ) >. ) = (Vtx ` G ) )
12		opiedgfv 16266	. . . . . . . . 9 |- ( ( (Vtx ` G ) e. _V /\ (iEdg ` G ) e. _V ) -> (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) = (iEdg ` G ) )
13	1, 2, 12	syl2anc 415	. . . . . . . 8 |- ( G e. W -> (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) = (iEdg ` G ) )
14	13	dmeqd 4983	. . . . . . 7 |- ( G e. W -> dom (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) = dom (iEdg ` G ) )
15	13	fveq1d 5697	. . . . . . . 8 |- ( G e. W -> ( (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) ` x ) = ( (iEdg ` G ) ` x ) )
16	15	eleq2d 2308	. . . . . . 7 |- ( G e. W -> ( u e. ( (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) ` x ) <-> u e. ( (iEdg ` G ) ` x ) ) )
17	14, 16	rabeqbidv 2816	. . . . . 6 |- ( G e. W -> { x e. dom (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) | u e. ( (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) ` x ) } = { x e. dom (iEdg ` G ) | u e. ( (iEdg ` G ) ` x ) } )
18	17	fveq2d 5699	. . . . 5 |- ( G e. W -> (♯ ` { x e. dom (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) | u e. ( (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) ` x ) } ) = (♯ ` { x e. dom (iEdg ` G ) | u e. ( (iEdg ` G ) ` x ) } ) )
19	15	eqeq1d 2247	. . . . . . 7 |- ( G e. W -> ( ( (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) ` x ) = { u } <-> ( (iEdg ` G ) ` x ) = { u } ) )
20	14, 19	rabeqbidv 2816	. . . . . 6 |- ( G e. W -> { x e. dom (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) | ( (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) ` x ) = { u } } = { x e. dom (iEdg ` G ) | ( (iEdg ` G ) ` x ) = { u } } )
21	20	fveq2d 5699	. . . . 5 |- ( G e. W -> (♯ ` { x e. dom (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) | ( (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) ` x ) = { u } } ) = (♯ ` { x e. dom (iEdg ` G ) | ( (iEdg ` G ) ` x ) = { u } } ) )
22	18, 21	oveq12d 6103	. . . 4 |- ( G e. W -> ( (♯ ` { x e. dom (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) | u e. ( (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) ` x ) } ) +e (♯ ` { x e. dom (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) | ( (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) ` x ) = { u } } ) ) = ( (♯ ` { x e. dom (iEdg ` G ) | u e. ( (iEdg ` G ) ` x ) } ) +e (♯ ` { x e. dom (iEdg ` G ) | ( (iEdg ` G ) ` x ) = { u } } ) ) )
23	11, 22	mpteq12dv 4213	. . 3 |- ( G e. W -> ( u e. (Vtx ` <. (Vtx ` G ) , (iEdg ` G ) >. ) |-> ( (♯ ` { x e. dom (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) | u e. ( (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) ` x ) } ) +e (♯ ` { x e. dom (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) | ( (iEdg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) ` x ) = { u } } ) ) ) = ( u e. (Vtx ` G ) |-> ( (♯ ` { x e. dom (iEdg ` G ) | u e. ( (iEdg ` G ) ` x ) } ) +e (♯ ` { x e. dom (iEdg ` G ) | ( (iEdg ` G ) ` x ) = { u } } ) ) ) )
24	9, 23	eqtrd 2271	. 2 |- ( G e. W -> (VtxDeg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) = ( u e. (Vtx ` G ) |-> ( (♯ ` { x e. dom (iEdg ` G ) | u e. ( (iEdg ` G ) ` x ) } ) +e (♯ ` { x e. dom (iEdg ` G ) | ( (iEdg ` G ) ` x ) = { u } } ) ) ) )
25		df-ov 6088	. . 3 |- ( (Vtx ` G )VtxDeg (iEdg ` G ) ) = (VtxDeg ` <. (Vtx ` G ) , (iEdg ` G ) >. )
26	25	a1i 9	. 2 |- ( G e. W -> ( (Vtx ` G )VtxDeg (iEdg ` G ) ) = (VtxDeg ` <. (Vtx ` G ) , (iEdg ` G ) >. ) )
27		eqid 2238	. . 3 |- (Vtx ` G ) = (Vtx ` G )
28		eqid 2238	. . 3 |- (iEdg ` G ) = (iEdg ` G )
29		eqid 2238	. . 3 |- dom (iEdg ` G ) = dom (iEdg ` G )
30	27, 28, 29	vtxdgfval 16529	. 2 |- ( G e. W -> (VtxDeg ` G ) = ( u e. (Vtx ` G ) |-> ( (♯ ` { x e. dom (iEdg ` G ) | u e. ( (iEdg ` G ) ` x ) } ) +e (♯ ` { x e. dom (iEdg ` G ) | ( (iEdg ` G ) ` x ) = { u } } ) ) ) )
31	24, 26, 30	3eqtr4rd 2282	1 |- ( G e. W -> (VtxDeg ` G ) = ( (Vtx ` G )VtxDeg (iEdg ` G ) ) )

This proof depends on syntax axioms:   -> wi 4   = wceq 1402   e. wcel 2209   {crab 2532   _Vcvv 2821   {csn 3709   <.cop 3712   |-> cmpt 4192   dom cdm 4774   ` cfv 5377  (class class class)co 6085   +ecxad 10172  ♯chash 11214  Vtxcvtx 16253  iEdgciedg 16254  VtxDegcvtxdg 16527

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 623  ax-in2 624  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-coll 4246  ax-sep 4249  ax-pow 4311  ax-pr 4346  ax-un 4578  ax-setind 4684  ax-cnex 8270  ax-resscn 8271  ax-1cn 8272  ax-1re 8273  ax-icn 8274  ax-addcl 8275  ax-addrcl 8276  ax-mulcl 8277  ax-addcom 8279  ax-mulcom 8280  ax-addass 8281  ax-mulass 8282  ax-distr 8283  ax-i2m1 8284  ax-1rid 8286  ax-0id 8287  ax-rnegex 8288  ax-cnre 8290

This proof depends on definitions:  df-bi 117  df-3an 1011  df-tru 1405  df-fal 1408  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ne 2421  df-ral 2533  df-rex 2534  df-reu 2535  df-rab 2537  df-v 2823  df-sbc 3052  df-csb 3148  df-dif 3222  df-un 3224  df-in 3226  df-ss 3233  df-if 3639  df-pw 3690  df-sn 3715  df-pr 3716  df-op 3718  df-uni 3936  df-int 3971  df-iun 4014  df-br 4131  df-opab 4193  df-mpt 4194  df-id 4438  df-xp 4780  df-rel 4781  df-cnv 4782  df-co 4783  df-dm 4784  df-rn 4785  df-res 4786  df-ima 4787  df-iota 5337  df-fun 5379  df-fn 5380  df-f 5381  df-f1 5382  df-fo 5383  df-f1o 5384  df-fv 5385  df-riota 6038  df-ov 6088  df-oprab 6089  df-mpo 6090  df-1st 6374  df-2nd 6375  df-sub 8499  df-inn 9305  df-2 9363  df-3 9364  df-4 9365  df-5 9366  df-6 9367  df-7 9368  df-8 9369  df-9 9370  df-n0 9564  df-dec 9778  df-ndx 13355  df-slot 13356  df-base 13358  df-edgf 16246  df-vtx 16255  df-iedg 16256  df-vtxdg 16528

This theorem is used by: (None)