Pascal's Triangle is able to generate artistic geometric patterns. To do so, choose a remainder. For each number in the triangle, shade that number a different colour for each different remainder. The applet below allows you to try this. For best results, use a modulus between 2 and 16.
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After trying this applet for a few different moduli, you may have noticed some interesting things. For example, the patterns produced by prime numbers are simpler than those produced by composite numbers.