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About unakade

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  1. A miraculous voyage

    But, how can it be a tetrahedron? The cities are just 5 miles away. Any 4 points on the surface of the earth which are also the vertices of a tetrahedron must be at a distance of 1.63 times the radius of the earth (which is about 6500 miles!!!).
  2. Out of respect to Bonanova--Fibonacci

    I am not quite sure about this because I did not find numbers a and b which give 216. Also, on wikipedia (http://en.wikipedia.org/wiki/Congruum), a list of first few congrua is given which does not contain 216. So, maybe 216 cannot be represented in this way. I did not find any other flaw in your argument.