1998 IMO Problems/Problem 6

Problem

Determine the least possible value of $f(1998),$ where $f:\Bbb{N}\to \Bbb{N}$ is a function such that for all $m,n\in {\Bbb N}$ ,

$f\left( n^{2}f(m)\right) =m\left( f(n)\right) ^{2}.$

1998 IMO (Problems) • Resources
Preceded by Problem 5	1 • 2 • 3 • 4 • 5 • 6	Followed by Last Question
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