A unit fraction is a fraction with numerator 1. Examples of unit fractions include 1/2, 1/3, 1/12, and 1/123456. The famous Rhind
papyrus, dated to around 1650 BC, discusses unit fractions and contains a table of
representations of 
as a sum of distinct unit fractions for odd 
between 5 and 101. As a result, sums of unit fractions are
now known as Egyptian fractions.
Bloom and van Doorn (2026) give a human exposition of OpenAI's short Egyptian fraction result. Every rational number 
with integers 
is a sum of 
distinct positive unit fractions, and the number of
representations of 1 by exactly 
distinct positive unit fractions grows doubly exponentially
in 
.
