Project Euler Problem #026: Reciprocal cycles

(Problem Link)

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.