Project Euler/40

Champernowne's Constant

Problem Statement

An irrational decimal fraction is created by concatenating the positive integers:

$0.12345678910{\color {red}\mathbf {1} }112131415161718192021\cdots$

It can be seen that the 12th digit of the fractional part is 1

If $d_{n}$ represents the nth digit of the fractional part, find the value of the following expression.

$d_{1}\times d_{10}\times d_{100}\times d_{1000}\times d_{10000}\times d_{100000}\times d_{1000000}$

Solution

Project Euler/40/Solution