Investigate what happens when you add house numbers along a street in different ways.
Can you complete this jigsaw of the multiplication square?
Can you see how these factor-multiple chains work? Find the chain which contains the smallest possible numbers. How about the largest possible numbers?
What do the numbers shaded in blue on this hundred square have in common? What do you notice about the pink numbers? How about the shaded numbers in the other squares?
Take a look at the multiplication square. The first eleven triangle numbers have been identified. Can you see a pattern? Does the pattern continue?
Can you describe this route to infinity? Where will the arrows take you next?
Delight your friends with this cunning trick! Can you explain how it works?