Combinatorics

  • Tangles
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    Tangles

    A personal investigation of Conway's Rational Tangles. What were the interesting questions that needed to be asked, and where did they lead?
  • Symmetric Tangles
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    Symmetric Tangles

    The tangles created by the twists and turns of the Conway rope trick are surprisingly symmetrical. Here's why!
  • Placeholder: several colourful numbers
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    Binomial Coefficients

    An introduction to the binomial coefficient, and exploration of some of the formulae it satisfies.

  • An Investigation Based on Score
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    An Investigation Based on Score

    Class 2YP from Madras College was inspired by the problem in NRICH to work out in how many ways the number 1999 could be expressed as the sum of 3 odd numbers, and this is their solution.

  • Transitivity
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    Transitivity

    Suppose A always beats B and B always beats C, then would you expect A to beat C? Not always! What seems obvious is not always true. Results always need to be proved in mathematics.