olymmath

PL-OM 2001

Polish Mathematical Olympiad 2001.

Other problems

Problem 3

A sequence x0=Ax_0=A and x1=Bx_1=B and xn+2=xn+1+xnx_{n+2}=x_{n+1} +x_n is called a Fibonacci type sequence. Call a number CC a repeated value if xt=xs=cx_t=x_s=c for tt different from ss . Prove one can choose AA and BB to have as many repeated value as one likes but never infinite.