International Mathematical Olympiads

Functions, Polynomials, and Sequences (136 pages)

My 9 Problems on International Mathematical Olympiads

List of the proposing countries of the IMO problems [1988 – 2017]

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Infinity (204 pages, with Tom Lovering, and Cosmin Pohoata)

Problems in Elementary Number Theory (87 pages, with Peter Vandendriessche) and Solutions

The International Mathematical Olympiad (IMO) is an annual six-problem mathematical olympiad for pre-college students. Each participating country may submit problems to a Problem Selection Committee which reduces the submitted problems to a shortlist. I am the unique Korean IMO problem composer since 1988 when Korea first participated at IMO. The other distinguished IMO problem composers include David Monk [United Kingdom, 14 Problems, 1968–1998] and Jan van de Craats [Netherlands, 11 Problems, 1974–1985].