Tower of cubes
Source: 2006 AIME I -- Question 11
March 8, 2006
geometry3D geometryinductionmodular arithmeticratioAMCAIME
Problem Statement
A collection of 8 cubes consists of one cube with edge-length for each integer A tower is to be built using all 8 cubes according to the rules:
Any cube may be the bottom cube in the tower.
The cube immediately on top of a cube with edge-length must have edge-length at most
Let be the number of different towers than can be constructed. What is the remainder when is divided by 1000?