
Triangle numbers
Take a look at the multiplication square. The first eleven triangle numbers have been identified. Can you see a pattern? Does the pattern continue?

Seven squares
Watch these videos to see how Phoebe, Alice and Luke chose to draw 7 squares. How would they draw 100?

Triangular clock

What numbers can we make now?
Imagine we have four bags containing numbers from a sequence. What numbers can we make now?

Spaces for exploration
Alf Coles writes about how he tries to create 'spaces for exploration' for the students in his classrooms.

Night watchmen

What a coincidence!

Train spotters' paradise

Elevenses
How many pairs of numbers can you find that add up to a multiple of 11? Do you notice anything interesting about your results?


Teaching patterns and sequences

Tower of Hanoi
The Tower of Hanoi is an ancient mathematical challenge. Working on the building blocks may help you to explain the patterns you notice.


Days and dates
Investigate how you can work out what day of the week your birthday will be on next year, and the year after...

Shifting times tables
Can you find a way to identify times tables after they have been shifted up or down?

Hexagon line

Summing consecutive numbers
15 = 7 + 8 and 10 = 1 + 2 + 3 + 4. Can you say which numbers can be expressed as the sum of two or more consecutive integers?

Pattern snake


1 step 2 step
Liam's house has a staircase with 12 steps. He can go down the steps one at a time or two at time. In how many different ways can Liam go down the 12 steps?

Knights and knaves

How many rectangles?

Frogs
How many moves does it take to swap over some red and blue frogs? Do you have a method?


Knockdown
Pegs numbered 1 to 50 are placed in a row. Alternate pegs are knocked down, and this process is repeated. What is the number of the last peg to be knocked down?

Even up
Consider all of the five digit numbers which we can form using only the digits 2, 4, 6 and 8. If these numbers are arranged in ascending order, what is the 512th number?

Charlie's delightful machine
Here is a machine with four coloured lights. Can you develop a strategy to work out the rules controlling each light?


Picturing triangular numbers
What do you notice about the sum of two identical triangular numbers?

Fibonacci deduction

Doubly consecutive sums

Picturing square numbers
Square numbers can be represented as the sum of consecutive odd numbers. What is the sum of 1 + 3 + ..... + 149 + 151 + 153?

Fruit line-up


Seven squares - group-worthy task

Printing error


Coordinate patterns
Charlie and Alison have been drawing patterns on coordinate grids. Can you picture where the patterns lead?


Squares in rectangles
A 2 by 3 rectangle contains 8 squares and a 3 by 4 rectangle contains 20 squares. What size rectangle(s) contain(s) exactly 100 squares? Can you find them all?

What numbers can we make?
Imagine we have four bags containing a large number of 1s, 4s, 7s and 10s. What numbers can we make?

Patterns and sequences - short problems

Street lamps

Odds, evens and more evens
Alison, Bernard and Charlie have been exploring sequences of odd and even numbers, which raise some intriguing questions...




Attractive tablecloths
Charlie likes tablecloths that use as many colours as possible, but insists that his tablecloths have some symmetry. Can you work out how many colours he needs for different tablecloth designs?

Ordered sums
Let a(n) be the number of ways of expressing the integer n as an ordered sum of 1's and 2's. Let b(n) be the number of ways of expressing n as an ordered sum of integers greater than 1. (i) Calculate a(n) and b(n) for n<8. What do you notice about these sequences? (ii) Find a relation between a(p) and b(q). (iii) Prove your conjectures.

Painted cube
Imagine a large cube made from small red cubes being dropped into a pot of yellow paint. How many of the small cubes will have yellow paint on their faces?

12345



Mystic rose
Use the animation to help you work out how many lines are needed to draw mystic roses of different sizes.

Partly painted cube
Jo made a cube from some smaller cubes, painted some of the faces of the large cube, and then took it apart again. 45 small cubes had no paint on them at all. How many small cubes did Jo use?

A little light thinking
Here is a machine with four coloured lights. Can you make two lights switch on at once? Three lights? All four lights?

Newspaper sheets

Steel cables
Some students have been working out the number of strands needed for different sizes of cable. Can you make sense of their solutions?


Collatz 13

Collatz-ish

Trolley park

Picture story
Can you see how this picture illustrates the formula for the sum of the first six cube numbers?