回复：Can you tell me why "601"?
aisanguo
2009-01-08 19:14:36
( reads)
13-6=7;
41-13=28=7*4
153-41=112=7*(4^2)
601-153=448=7*(4^3)
...
13-6=7;
41-13=28=7*4
153-41=112=7*(4^2)
601-153=448=7*(4^3)
...
rosejoy
2009-01-08 19:43:05佩服! 佩服! 佩服!