figuralnumbers
nounUK /ˈfɪɡərəl ˈnʌmbəz/
US /ˈfɪɡjərəl ˈnʌmbərz/
Figural numbers are numbers you can make into a shape with dots.
The teacher showed us that ten is a figural number because we can arrange ten dots into a triangle.
OTHER MEANINGS
2. Numbers that can be shown as a regular pattern of dots or points.
Square numbers like 4, 9, and 16 are figural numbers you can draw as squares.
3. A type of number studied in old math books that grows by adding layers of dots.
Ancient mathematicians wrote about figural numbers and their dot pictures.
4. Numbers linked to shapes such as triangles, squares, or pentagons.
Triangular figural numbers include 1, 3, 6, and 10.