MathDB
2023 Fall Theme p1C

Source:

December 23, 2023
2023FAlLthemegeo

Problem Statement

How many distinct triangles are there with prime side lengths and perimeter 100100?
Proposed by Muztaba Syed
Solution. 0\boxed{0} As the perimeter is even, 11 of the sides must be 22. Thus, the other 22 sides are congruent by Triangle Inequality. Thus, for the perimeter to be 100100, both of the other sides must be 4949, but as 4949 is obviously composite, the answer is thus 0\boxed{0}.