let x1, x2, x3, x5, x6, x7 be non pair set ; InputVertices (STC0IIStr (x1,x2,x3,x5,x6,x7)) = {x1,x2,x3,x5,x6,x7}
set S = STC0IIStr (x1,x2,x3,x5,x6,x7);
set S1 = BitGFA0Str (x1,x2,x3);
set S2 = BitGFA0Str (x5,x6,x7);
A1:
( InputVertices (BitGFA0Str (x1,x2,x3)) = {x1,x2,x3} & InputVertices (BitGFA0Str (x5,x6,x7)) = {x5,x6,x7} )
by GFACIRC1:34;
( InnerVertices (BitGFA0Str (x1,x2,x3)) is Relation & InnerVertices (BitGFA0Str (x5,x6,x7)) is Relation )
;
hence InputVertices (STC0IIStr (x1,x2,x3,x5,x6,x7)) =
{x1,x2,x3} \/ {x5,x6,x7}
by A1, FACIRC_1:7
.=
{x1,x2,x3,x5,x6,x7}
by ENUMSET1:13
;
verum