Every vertex has an even degree, yet the picture cannot be drawn with a single stroke.
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On the cover: cellular automata
Discover the meaning of the coloured squares on the cover of issue 13
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A great start to the month of Maying
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Have a go at these puzzles, adequate for your holidays!
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Hunting for polydivisibles
The search for polydivisible numbers in different bases: how many can you find?