MathDB
Counter Balance

Source: 1999 National High School Mathematics League, Exam Two, Problem 3

March 10, 2020

Problem Statement

nn is a given positive integer, such that it’s possible to weigh out the mass of any product weighing 1,2,3,,ng1,2,3,\cdots ,n\text{g} with a counter balance and kk counterweights, whose weights are positive integers. (a) Find f(n)f(n): the minumum value of kk. (b) Find all possible number of n,n, such that the mass of f(n)f(n) counterweights is uniquely determined.