sets of sequences, M<= 2n-4 (VII Soros Olympiad 2000-01 R1 11.7)
Source:
July 29, 2021
algebraSequenceSequences
Problem Statement
Consider all possible functions defined for and taking values . We denote the set of such functions by By we denote the subset of consisting of functions whose value changes exactly by (in one direction or another) when the argument changes by . Prove that if , then among the functions from of the set , there is a function that coincides at least at one point with any function from . Specify at least one such function. Prove that if , then there is no such function.