numbere in a triangular table
Source: Czech and Slovak Olympiad 1985, National Round, Problem 5
September 11, 2024
combinatorics
Problem Statement
A triangular table with rows and columns is given, the -th row ends with a field in the -th column. In each field of the table, some of the numbers are written such that for each all the numbers occur in the union of the -th row and the -th column.
Prove that for odd , each of the numbers is written in the last box of a row.
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