Fibonacci sequence

  • Plus or Minus
    problem

    Plus or minus

    Age
    16 to 18
    Challenge level
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    Make and prove a conjecture about the value of the product of the Fibonacci numbers $F_{n+1}F_{n-1}$.
  • Room Doubling
    problem

    Room doubling

    Age
    7 to 11
    Challenge level
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    Investigate the different ways you could split up these rooms so that you have double the number.
  • Colour Building
    problem

    Colour building

    Age
    11 to 14
    Challenge level
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    Using only the red and white rods, how many different ways are there to make up the other rods?
  • 1 Step 2 Step
    problem

    1 step 2 step

    Age
    11 to 14
    Challenge level
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    Liam's house has a staircase with 12 steps. He can go down the steps one at a time or two at time. In how many different ways can Liam go down the 12 steps?

  • Fibonacci Surprises
    problem

    Fibonacci surprises

    Age
    11 to 14
    Challenge level
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    Play around with the Fibonacci sequence and discover some surprising results!

  • Fibs
    problem

    Fibs

    Age
    11 to 14
    Challenge level
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    The well known Fibonacci sequence is 1 ,1, 2, 3, 5, 8, 13, 21.... How many Fibonacci sequences can you find containing the number 196 as one of the terms?
  • Last Biscuit
    game

    Last biscuit

    Age
    11 to 18
    Challenge level
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    Can you find a strategy that ensures you get to take the last biscuit in this game?

  • Building Gnomons
    problem

    Building gnomons

    Age
    14 to 16
    Challenge level
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    Build gnomons that are related to the Fibonacci sequence and try to explain why this is possible.
  • Gnomon dimensions
    problem

    Gnomon dimensions

    Age
    14 to 16
    Challenge level
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    These gnomons appear to have more than a passing connection with the Fibonacci sequence. This problem ask you to investigate some of these connections.
  • Ordered Sums
    problem

    Ordered sums

    Age
    14 to 16
    Challenge level
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    Let a(n) be the number of ways of expressing the integer n as an ordered sum of 1's and 2's. Let b(n) be the number of ways of expressing n as an ordered sum of integers greater than 1. (i) Calculate a(n) and b(n) for n<8. What do you notice about these sequences? (ii) Find a relation between a(p) and b(q). (iii) Prove your conjectures.