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arXiv · 2409.17117

Counting Triangles in Triangles

Jim Propp·Adam Propp-Gubin
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Abstract

We give a formula for counting the triangles in a picture consisting of the three sides of a triangle and some cevians. This lets us prove statements that are claimed without proof in the Online Encyclopedia of Integer Sequences and some popular YouTube videos, and also prove some new results. We also give formulas that apply when the cevians cut each side into equal-length pieces.

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Jim Propp, Adam Propp-Gubin. 2024-10-25. Counting Triangles in Triangles. https://arxiv.org/abs/2409.17117

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