Some helpful links:

Specific to this problem:

Those sites help me solve pretty much all the Project Euler problems. Of course, it does help to have some familiarity with the basics of number theory and combinatorics. Google and Wikipedia can help you with that too.

Here's my solution (runs in about 0.6 sec):

<Reveal this spoiler or all in this thread>

In reply to Re: Learning math and efficient algorithms using perl by rhesa
in thread Learning math and efficient algorithms using perl by andreas1234567

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