Metamath Proof Explorer


Theorem 0uhgrsubgr

Description: The null graph (as hypergraph) is a subgraph of all graphs. (Contributed by AV, 17-Nov-2020) (Proof shortened by AV, 28-Nov-2020)

Ref Expression
Assertion 0uhgrsubgr GWSUHGraphVtxS=SSubGraphG

Proof

Step Hyp Ref Expression
1 3simpa GWSUHGraphVtxS=GWSUHGraph
2 0ss VtxG
3 sseq1 VtxS=VtxSVtxGVtxG
4 2 3 mpbiri VtxS=VtxSVtxG
5 4 3ad2ant3 GWSUHGraphVtxS=VtxSVtxG
6 eqid iEdgS=iEdgS
7 6 uhgrfun SUHGraphFuniEdgS
8 7 3ad2ant2 GWSUHGraphVtxS=FuniEdgS
9 edgval EdgS=raniEdgS
10 uhgr0vb SUHGraphVtxS=SUHGraphiEdgS=
11 rneq iEdgS=raniEdgS=ran
12 rn0 ran=
13 11 12 eqtrdi iEdgS=raniEdgS=
14 10 13 syl6bi SUHGraphVtxS=SUHGraphraniEdgS=
15 14 ex SUHGraphVtxS=SUHGraphraniEdgS=
16 15 pm2.43a SUHGraphVtxS=raniEdgS=
17 16 a1i GWSUHGraphVtxS=raniEdgS=
18 17 3imp GWSUHGraphVtxS=raniEdgS=
19 9 18 eqtrid GWSUHGraphVtxS=EdgS=
20 egrsubgr GWSUHGraphVtxSVtxGFuniEdgSEdgS=SSubGraphG
21 1 5 8 19 20 syl112anc GWSUHGraphVtxS=SSubGraphG