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What's this on your Etch-A-Sketch?

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Meet Jason Padgett.

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The inner boundary of pi is f(x) = x sin (π/x).

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Oh, my god.

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How is this possible?

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they cannot be solved without a key.

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This is what's known as a "look-and-say sequence."

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Unlike many number sequences,

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this relies not on some mathematical property of the numbers themselves,

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