A spaceship travels in a straight line. It doubles its speed after half a minute, doubles it again after another quarter of a minute, and continues successively to double it after half of the last interval. Where is it at one minute? It is neither infinitely far away, nor at any finite distance either. Read the rest of this entry »

## The Spaceship

27/07/2012## Just number

10/04/2012## 500 Sudoku Puzzles

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