let G2 be inducedSubgraph of G,(G .reachableFrom v); :: thesis: G2 is Component-like
A1: the_Vertices_of G2 = G .reachableFrom v by GLIB_000:def 37;
A2: the_Edges_of G2 = G .edgesBetween (G .reachableFrom v) by GLIB_000:def 37;
A3: now :: thesis: for G3 being connected Subgraph of G holds not G2 c< G3
A4: v in the_Vertices_of G2 by A1, Lm1;
given G3 being connected Subgraph of G such that A5: G2 c< G3 ; :: thesis: contradiction
G2 c= G3 by A5, GLIB_000:def 36;
then A6: G2 is Subgraph of G3 by GLIB_000:def 35;
then A7: the_Vertices_of G2 c= the_Vertices_of G3 by GLIB_000:def 32;
A8: now :: thesis: for x being object holds
( not x in the_Vertices_of G3 or x in the_Vertices_of G2 )
given x being object such that A9: x in the_Vertices_of G3 and
A10: not x in the_Vertices_of G2 ; :: thesis: contradiction
consider W being Walk of G3 such that
A11: W is_Walk_from v,x by A4, A7, A9, Def1;
reconsider W = W as Walk of G by GLIB_001:167;
W is_Walk_from v,x by A11, GLIB_001:19;
hence contradiction by A1, A10, Def5; :: thesis: verum
end;
A12: the_Vertices_of G2 c= the_Vertices_of G3 by A6, GLIB_000:def 32;
now :: thesis: contradictionend;
hence contradiction ; :: thesis: verum
end;
now :: thesis: for x, y being Vertex of G2 ex W being Walk of G2 st W is_Walk_from x,yend;
then G2 is connected ;
hence G2 is Component-like by A3; :: thesis: verum