1 divided by any multiple of 7 will return repeated strings of 6 numbers (possibly after a few random numbers at the beginning), except 7^2 or any multiple of that. Why is that?
The reciprocal of 7 and ALL the multiples of 7 will repeat sooner or later because they are all rational numbers. Even your 1/49 repeats every 42 digits. You may not see it on your calculator because the display is limited on most calculators to 10 to 20 digits. So, 1/49 =
0.020408163265306122448979591836734693877551020408163265306.................etc.
