Project Euler Problem 40 Solution

Question

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

0.123456789101112131415161718192021...0.123456789101112131415161718192021...

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

If dnd_n represents the nth digit of the fractional part, find the value of the following expression.

d1×d10×d100×d1000×d10000×d100000×d1000000d_1 \times d_{10} \times d_{100} \times d_{1000} \times d_{10000} \times d_{100000} \times d_{1000000}

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