The Spaceship

27/07/2012

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 »

Just number

10/04/2012

Soltion

500 Sudoku Puzzles

30/03/2012

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