theorem Th25: :: FSCIRC_2:25

for x, y, c being set st x <> [<*y,c*>,and2] & y <> [<*x,c*>,and2a] & c <> [<*x,y*>,and2a] & c <> [<*x,y*>,'xor'] holds
for s being State of (BitSubtracterWithBorrowCirc (x,y,c)) holds Following (s,2) is stable