TRY ANGULATE
A crochet representation of square numbers and triangular numbers, consisting of 225 circles.
Triangular numbers are what you get when you add conscecutive numbers. The circles with dark centres are
1 + 2 + 3 + 4 ……. +14 = 105
The circles without dark centres are
1 + 2 + 3 + 4 ……. +15 = 120
Add two consecutive triangular numbers and you get a square number.
105 + 120 = 225, which is the square of 15