The Forgotten Flexagon - Numberphile
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Stones on an Infinite Chessboard - Numberphile
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Hexaflexaflakes
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Way Bigger Than Graham's Number (Goodstein Sequence) - Numberphile
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A New Discovery about Dodecahedrons - Numberphile
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Euler Squares - Numberphile
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Beautiful Trigonometry - Numberphile
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How To Make a Hexaflexagon: The Definitive Guide
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