# Blog

## Nifty triangle numbers

By Ariel Marcy, 6 November 2023

Difficulty: Fun Triangular numbers are numbers that can be formed into a triangle. For example, 3 is a triangular number with 2 dots on the bottom row and 1 dot on top row forming an equilateral triangle of 3 dots. 6 is the next triangular number with 3 dots on the bottom, 2 dots in […]

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## How many squares fit in a rectangle?

By David Shaw, 10 March 2022

It might seem like a silly question to ask. After all, it depends on how big the rectangle is, and also the size of the squares you’re packing it with. With a big rectangle and small squares, you could fit a million, a billion or even more. But what if you have infinity squares? Is […]

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## Straight line heart

By David Shaw, 6 November 2015

This simple pattern reveals a heart from a circle and a lot of straight lines!

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