# Problem 26: Reciprocal cycles

A unit fraction contains 1 in the numerator. The decimal representation
of the unit fractions with denominators 2 to 10 are given: 

>   1/2 = 0.5
>   1/3 = 0.(3) 
>   1/4 = 0.25 
>   1/5 = 0.2 
>   1/6 = 0.1(6) 
>   1/7 = 0.(142857) 
>   1/8 = 0.125
>   1/9 = 0.(1)
>   1/10 = 0.1

Where 0.1(6) means 0.166666..., and has a 1-digit recurring cycle. It can be
seen that 1/7 has a 6-digit recurring cycle. Find the value of d < 1000 for 
which 1/d contains the longest recurring cycle in its decimal fraction part.