5-Mar-1995

Unsolved Problem 10:

If n is an integer larger than 1, must there be integers x, y, and z, such that 4/n=1/x+1/y+1/z?

A number of the form 1/x where x is an integer is called an Egyptian fraction.
Thus, we want to know if 4/n is always the sum of three Egyptian fractions, for n>1.

Reference:

[Erdos 1980]
Paul Erdös and Ronald L. Graham, Old and New Problems and Results in Combinatorial Number Theory. L'Enseignement Mathématique. Geneva, Switzerland: 1980. Page 44.
Egyptian Fractions
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