MathDB
Existence of a polynomial

Source: China TST 2006

June 18, 2006
algebrapolynomialinductionmodular arithmeticpigeonhole principlealgebra unsolved

Problem Statement

Let kk be an odd number that is greater than or equal to 33. Prove that there exists a kthk^{th}-degree integer-valued polynomial with non-integer-coefficients that has the following properties: (1) f(0)=0f(0)=0 and f(1)=1f(1)=1; and. (2) There exist infinitely many positive integers nn so that if the following equation: n=f(x1)++f(xs), n= f(x_1)+\cdots+f(x_s), has integer solutions x1,x2,,xsx_1, x_2, \dots, x_s, then s2k1s \geq 2^k-1.