let G1 be _finite real-weighted WGraph; for n being Nat
for G2 being inducedSubgraph of G1,(((PRIM:CompSeq G1) . n) `1) holds G2 is connected
let n be Nat; for G2 being inducedSubgraph of G1,(((PRIM:CompSeq G1) . n) `1) holds G2 is connected
set V = ((PRIM:CompSeq G1) . n) `1 ;
let G2 be inducedSubgraph of G1,(((PRIM:CompSeq G1) . n) `1); G2 is connected
reconsider V = ((PRIM:CompSeq G1) . n) `1 as non empty Subset of (the_Vertices_of G1) by Th30;
set E = ((PRIM:CompSeq G1) . n) `2 ;
reconsider E = ((PRIM:CompSeq G1) . n) `2 as Subset of (G1 .edgesBetween V) by Th30;
set G3 = the inducedSubgraph of G1,V,E;
A1:
( the_Vertices_of the inducedSubgraph of G1,V,E = V & the_Vertices_of G2 = V )
by GLIB_000:def 37;
( the_Edges_of the inducedSubgraph of G1,V,E = E & the_Edges_of G2 = G1 .edgesBetween V )
by GLIB_000:def 37;
then reconsider G3 = the inducedSubgraph of G1,V,E as Subgraph of G2 by A1, GLIB_000:44;
A2:
G3 is spanning
by A1;
G3 is connected
by Th31;
hence
G2 is connected
by A2, GLIB_002:23; verum