Sunday July 31, 2011
Here, you'll be investigating an interesting property of a numerical sequence.
A number chain is created by continuously adding the square of the digits in a number to form a new number until it has been seen before.

For example,


Therefore any chain that arrives at 1 or 89 will become stuck in an endless loop. What is most significant is that every starting number will eventually arrive at 1 or 89.

How many starting numbers below one million will arrive at 89?

(This problem and its text come from Project Euler).
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Challenge Resources:
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