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# The Number of the Day: 7 (Plus a Contest)

The Wow-I-Feel-Old Number of the Day: Between them, the three Hanson brothers now have seven children.

Related Giveaway: Want to see your name in pixels? Would you like to contribute to a future Number of the Day post? Can we interest you in a DVD copy of The Book of Eli? If you answered yes to at least a couple of those questions, leave us a comment with an amazing statistic (with a link to your source). We'll pick 5 winners and probably run your facts after InternWill goes back to school.

[Source: The current issue of Rolling Stone (page 30). See previous Numbers of the Day here.]

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This Puzzling Math Brain Teaser Has a Simple Solution
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Fans of number-based brainteasers might find themselves pleasantly stumped by the following question, posed by TED-Ed’s Alex Gendler: Which sequence of integers comes next?

1, 11, 21, 1211, 111221, ?

Mathematicians may recognize this pattern as a specific type of number sequence—called a “look-and-say sequence"—that yields a distinct pattern. As for those who aren't number enthusiasts, they should try reading the numbers they see aloud (so that 1 becomes "one one," 11 is "two ones," 21 is "one two, one one,” and so on) to figure the answer.

Still can’t crack the code? Learn the surprisingly simple secret to solving the sequence by watching the video below.