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Project Euler 80: Calculating the digital sum of the decimal digits of irrational square roots.

Project Euler 80: Calculating the digital sum of the decimal digits of irrational square roots.

Based on the headline Problem 80 of Project Euler sounds easy. It seems we just have to calculate the square root to a certain precision. So lets look at the problem description

It is well known that if the square root of a natural number is not an integer, then it is irrational. The decimal expansion of such square roots is infinite without any repeating pattern at all.

The square root of two is 1.41421356237309504880…, and the digital sum of the first one hundred decimal digits is 475.

For the first one hundred natural numbers, find the total of the digital sums of the first one hundred decimal digits for all the irrational square roots.

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Posted by Kristian in Project Euler, 19 comments