Sad Combinatorics
Source: 2020 USOMO 5, by Carl Schildkraut
June 21, 2020
combinatoricsHi
Problem Statement
A finite set of points in the coordinate plane is called overdetermined if and there exists a nonzero polynomial , with real coefficients and of degree at most , satisfying for every point .
For each integer , find the largest integer (in terms of ) such that there exists a set of distinct points that is not overdetermined, but has overdetermined subsets. Proposed by Carl Schildkraut