MathDB
Old idea in a new context

Source: Vietnam TST 2024 P6

March 27, 2024
algebrapolynomial

Problem Statement

Let P(x)Z[x]P(x) \in \mathbb{Z}[x] be a polynomial. Determine all polynomials Q(x)Z[x]Q(x) \in \mathbb{Z}[x], such that for every positive integer nn, there exists a polynomial Rn(x)Z[x]R_n(x) \in \mathbb{Z}[x] satisfies Q(x)2n1=Rn(x)(P(x)2n1).Q(x)^{2n} - 1 = R_n(x)\left(P(x)^{2n} - 1\right).