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United States competition problems

Combinatorics Difficulty 5.0 AIME Find the answer United States

Problem:

Draw a rectangle. Connect the midpoints of the opposite sides to get 4 congruent rectangles. Connect the midpoints of the lower right rectangle for a total of 7 rectangles. Repeat this process infinitely. Let nn be the minimum number of colors we can assign to the rectangles so that no two rectangles sharing an edge have the same color and mm be the minimum number of colors we can assign to the rectangles so that no two rectangles sharing a corner have the same color. Find the ordered pair (n,m)(n, m).

A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.

Solution

Solution:

(3,4)(3,4).

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Source: MathNet, licensed CC-BY-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project.