let x, y, c be set ; :: thesis: ( [<*x,y*>,and2a ] in InnerVertices (BorrowStr x,y,c) & [<*y,c*>,and2 ] in InnerVertices (BorrowStr x,y,c) & [<*x,c*>,and2a ] in InnerVertices (BorrowStr x,y,c) )
( [<*x,y*>,and2a ] in InnerVertices (1GateCircStr <*x,y*>,and2a ) & [<*y,c*>,and2 ] in InnerVertices (1GateCircStr <*y,c*>,and2 ) ) by FACIRC_1:47;
then ( [<*x,c*>,and2a ] in InnerVertices (1GateCircStr <*x,c*>,and2a ) & [<*x,y*>,and2a ] in InnerVertices ((1GateCircStr <*x,y*>,and2a ) +* (1GateCircStr <*y,c*>,and2 )) & [<*y,c*>,and2 ] in InnerVertices ((1GateCircStr <*x,y*>,and2a ) +* (1GateCircStr <*y,c*>,and2 )) ) by FACIRC_1:21, FACIRC_1:47;
then ( [<*x,y*>,and2a ] in InnerVertices (BorrowIStr x,y,c) & [<*y,c*>,and2 ] in InnerVertices (BorrowIStr x,y,c) & [<*x,c*>,and2a ] in InnerVertices (BorrowIStr x,y,c) ) by FACIRC_1:21;
hence ( [<*x,y*>,and2a ] in InnerVertices (BorrowStr x,y,c) & [<*y,c*>,and2 ] in InnerVertices (BorrowStr x,y,c) & [<*x,c*>,and2a ] in InnerVertices (BorrowStr x,y,c) ) by FACIRC_1:21; :: thesis: verum