data/problems/40.yml
---
:id: 40
:name: Champernowne's constant
:url: https://projecteuler.net/problem=40
:content: |+
An irrational decimal fraction is created by concatenating the positive integers:
0.123456789101112131415161718192021...
It can be seen that the 12<sup>th</sup> digit of the fractional part is 1.
If _d_<sub><i>n</i></sub> represents the _n_<sup>th</sup> digit of the fractional part, find the value of the following expression.
_d_<sub>1</sub> × _d_<sub>10</sub> × _d_<sub>100</sub> × _d_<sub>1000</sub> × _d_<sub>10000</sub> × _d_<sub>100000</sub> × _d_<sub>1000000</sub>