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## Still More Quick Snippets

Published on Thursday, November 11, 2010 in , , , ,

November already?!? Didn't 2010 just start? I guess I'd better get the November snippets in before it's suddenly New Year's Eve.

• If you liked the Scott Flansburg videos, I have some videos of people who specialize in the day of the week for any date feat for you. First, check out 6-year old William Dam, who is a very young human calendar.

Ever wonder how fast the human mind can calculate the day of the week? Back in June, Freddis Reyes Hernandez was able to give the day of the week for 74 dates. This was a world record until Jan Van Koningsveld did 78 dates in 1 minute in September!

Speaking of the day of the week for any date feat, I should mention that MindMagician.org just updated their Day For Any Date quizzer for improved readability and compatibility across various browsers.

• I've recently run across some sites with interesting mathematical tidbits. In the snippets section of Nerd Paradise, I found this interesting method for determining how many zeros a factorial will have. For example, 10! (10 factorial) = 10 × 9 × 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1 = 3628800, which has 2 zeroes. How many would say, 103! have?

Also, I've been enjoying Ben Vitale's number-focused blogs, Fun With Num3ers and More Fun With Num3ers. I was especially intrigued with this post, as I'd never realized that not only were all the odd square numbers 1 greater than a multiple of 8, but were also 1 greater than a multiple of 8 times a triangular number!

• If you've enjoyed my past posts about the Prisoner's Dilemma, check out JimBobJenkins' YouTube Channel, where William Spaniel offers a complete free course in game theory!

Don't forget to keep checking the Mind Your Decisions blog for more interesting game theory posts. Their most recent post concerns a Texas Hold 'Em paradox that will be very familiar to fans of Scam School's non-transitive scams.

That's all I have for now. Do you have any math- or memory-related links you'd like to share? Let's hear about them in comments!