MathDB
13rd ibmo - rep. dominicana 1998/q6.

Source: Spanish Communities

April 16, 2006
floor functionmodular arithmeticalgebra solvedalgebra

Problem Statement

Let λ\lambda the positive root of the equation t21998t1=0t^2-1998t-1=0. It is defined the sequence x0,x1,x2,,xn,x_0,x_1,x_2,\ldots,x_n,\ldots by x_0=1,\ x_{n+1}=\lfloor\lambda{x_n}\rfloor\mbox{ for }n=1,2\ldots Find the remainder of the division of x1998x_{1998} by 19981998. Note: x\lfloor{x}\rfloor is the greatest integer less than or equal to xx.