This is one where it would have been super helpful to have some answers to compare against. Beyond the initial few digits, I'm just assuming things are correct, which may not be true.
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A little late to the party (3am my time), but oh well! Here's my submission:
Full code w/ some tests: gist.github.com/kerrishotts/029c8f...
This is one where it would have been super helpful to have some answers to compare against. Beyond the initial few digits, I'm just assuming things are correct, which may not be true.