statement.html

problem 26 · 16 lines

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<p>A unit fraction contains $1$ in the numerator. The decimal representation of the unit fractions with denominators $2$ to $10$ are given:</p>
$$\begin{align}
1/2 &amp;= 0.5\\
1/3 &amp;=0.(3)\\
1/4 &amp;=0.25\\
1/5 &amp;= 0.2\\
1/6 &amp;= 0.1(6)\\
1/7 &amp;= 0.(142857)\\
1/8 &amp;= 0.125\\
1/9 &amp;= 0.(1)\\
1/10 &amp;= 0.1
\end{align}$$
<p>Where $0.1(6)$ means $0.166666\cdots$, and has a $1$-digit recurring cycle. It can be seen that $1/7$ has a $6$-digit recurring cycle.</p>
<p>Find the value of $d \lt 1000$ for which $1/d$ contains the longest recurring cycle in its decimal fraction part.</p>
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