1-1/2-1/4-1/8-1/16-1/32-1/64
=(1-1/2)-1/4-1/8-1/16-1/32-1/64
=1/2-1/4-1/8-1/16-1/32-1/64
=1/4-1/8-1/16-1/32-1/64
=1/8-1/16-1/32-1/64
=1/16-1/32-1/64
=1/32-1/64
=1/64
1-1/2-1/4-1/8-1/16-1/32-1/64
=(1-1/2)-1/4-1/8-1/16-1/32-1/64
=1/2-1/4-1/8-1/16-1/32-1/64
=1/4-1/8-1/16-1/32-1/64
=1/8-1/16-1/32-1/64
=1/16-1/32-1/64
=1/32-1/64
=1/64