History of mathematics · Maths EE idea · Accessible

Egyptian fractions

A research question to start from

Why can every fraction be written as a sum of distinct unit fractions, and how efficient is the greedy method?

A starting point, not your question: change the case, the comparison or the limit until it is yours. The research-question builder helps you check it.

Why it works as a maths EE

An ancient practice with a modern proof and algorithm analysis.

Mathematics you would need

  • Unit fractions
  • The greedy algorithm
  • Proof of termination
  • Bounds on denominators

Much of this goes beyond the DP course. That is expected in a maths EE, but you must understand and explain everything you use.

One possible line of attack

  1. Describe the historical use briefly.
  2. Prove the greedy algorithm terminates.
  3. Analyse how large denominators can get and compare with other methods.

Scope and difficulty

Accessible. Accessible.

Pitfalls

  • Too much history.
  • Termination not proved.

Where to start reading

Search a library catalogue or a university's open lecture notes for: Egyptian fractions greedy algorithm proof Fibonacci-Sylvester. Prefer textbooks, lecture notes and journal articles to a single website, and cite everything you use (how to reference a maths EE).

Make it your EE

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