List

Patterns and Sequences Short Problems

Picturing Triangular Numbers
problem
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Picturing Triangular Numbers

Age
11 to 14
Challenge level
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Triangular numbers can be represented by a triangular array of squares. What do you notice about the sum of identical triangle numbers?
Charlie's delightful machine
problem
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Charlie's delightful machine

Age
11 to 16
Challenge level
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Here is a machine with four coloured lights. Can you develop a strategy to work out the rules controlling each light?

Knockdown
problem

Knockdown

Age
11 to 14
Challenge level
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Weekly Problem 51 - 2016
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?
Suit Sequence
problem

Suit Sequence

Age
11 to 14
Challenge level
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A pattern repeats every six symbols. What are the 100th and 101st symbols?
Picturing Square Numbers
problem
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Picturing Square Numbers

Age
11 to 14
Challenge level
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Square numbers can be represented as the sum of consecutive odd numbers. What is the sum of 1 + 3 + ..... + 149 + 151 + 153?

Fibonacci Deduction
problem

Fibonacci Deduction

Age
11 to 14
Challenge level
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Leonard writes down a sequence of numbers. Can you find a formula to predict the seventh number in his sequence?
Doubly Consecutive Sums
problem

Doubly Consecutive Sums

Age
11 to 14
Challenge level
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How many numbers less than 2017 are both the sum of two consecutive integers and the sum of five consecutive integers?
Seven Squares - Group-worthy Task
problem
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Seven Squares - Group-worthy Task

Age
11 to 14
Challenge level
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Choose a couple of the sequences. Try to picture how to make the next, and the next, and the next... Can you describe your reasoning?
Fruit Line-Up
problem

Fruit Line-Up

Age
11 to 14
Challenge level
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This grocer wants to arrange his fruit in a particular order, can you help him?
Placeholder: several colourful numbers
problem

Square grid

Age
11 to 14
Challenge level
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Can you work out what fraction of this grid is shaded?
Coordinate Patterns
problem
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Coordinate Patterns

Age
11 to 14
Challenge level
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Charlie and Alison have been drawing patterns on coordinate grids. Can you picture where the patterns lead?
Printing Error
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Printing Error

Age
11 to 14
Challenge level
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Every third page number in this book has been omitted. Can you work out what number will be on the last page?
Placeholder: several colourful numbers
problem

Tiled Floor

Age
11 to 14
Challenge level
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This tiled floor has 109 purple tiles. How many tiles are there altogether?
Squares in rectangles
problem
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Squares in rectangles

Age
11 to 14
Challenge level
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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?
Many Matildas
problem

Many Matildas

Age
11 to 14
Challenge level
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MatildaMatildaMatil... What is the 1000th letter?
Street Lamps
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Street Lamps

Age
11 to 14
Challenge level
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Walking up a steep hill, I pass 10 equally spaced street lamps. How long do I take to walk from the first lamp to the last?
What numbers can we make?
problem
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What numbers can we make?

Age
11 to 14
Challenge level
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Imagine we have four bags containing a large number of 1s, 4s, 7s and 10s. What numbers can we make?

Triangle Numbers
problem
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Triangle Numbers

Age
11 to 14
Challenge level
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Take a look at the multiplication square. The first eleven triangle numbers have been identified. Can you see a pattern? Does the pattern continue?
Odds, Evens and More Evens
problem
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Odds, Evens and More Evens

Age
11 to 14
Challenge level
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Alison, Bernard and Charlie have been exploring sequences of odd and even numbers, which raise some intriguing questions...

spaces for exploration
article

spaces for exploration

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

Triangular Clock

Age
11 to 14
Challenge level
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Trinni rearanges numbers on a clock face so each adjacent pair add up to a triangle number... What number did she put where 6 would usually be?
Seven Squares
problem
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Seven Squares

Age
11 to 14
Challenge level
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Watch these videos to see how Phoebe, Alice and Luke chose to draw 7 squares. How would they draw 100?
Train Spotters' Paradise
article

Train Spotters' Paradise

Dave Hewitt suggests that there might be more to mathematics than looking at numerical results, finding patterns and generalising.
Night Watchmen
problem

Night Watchmen

Age
11 to 14
Challenge level
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Grannie's watch gains 30 minutes every hour, whilst Grandpa's watch loses 30 minutes every hour. What is the correct time when their watches next agree?
What numbers can we make now?
problem
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What numbers can we make now?

Age
11 to 14
Challenge level
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Imagine we have four bags containing numbers from a sequence. What numbers can we make now?

Teaching Patterns & Sequences
list

Teaching Patterns and Sequences

Age
11 to 16
These articles make the case for teaching in a way that emphasises understanding of underlying structures rather than simply noticing patterns in sequences.
Elevenses
problem
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Elevenses

Age
11 to 14
Challenge level
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How many pairs of numbers can you find that add up to a multiple of 11? Do you notice anything interesting about your results?
What a coincidence!
problem

What a coincidence!

Age
11 to 14
Challenge level
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Consider two arithmetic sequences: 1998, 2005, 2012,... and 1996, 2005, 2014,... Which numbers will appear in both?
Days and Dates
problem
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Days and Dates

Age
11 to 14
Challenge level
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Investigate how you can work out what day of the week your birthday will be on next year, and the year after...
Tower of Hanoi
problem
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Tower of Hanoi

Age
11 to 14
Challenge level
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The Tower of Hanoi is an ancient mathematical challenge. Working on the building blocks may help you to explain the patterns you notice.
Beach Huts
problem
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Beach Huts

Age
11 to 14
Challenge level
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Can you figure out how sequences of beach huts are generated?
Summing Consecutive Numbers
problem
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Summing Consecutive Numbers

Age
11 to 14
Challenge level
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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?

Shifting Times Tables
problem
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Shifting Times Tables

Age
11 to 14
Challenge level
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Can you find a way to identify times tables after they have been shifted up or down?

Growing Surprises
problem
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Growing Surprises

Age
11 to 14
Challenge level
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Can you find the connections between linear and quadratic patterns?
1 Step 2 Step
problem
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1 Step 2 Step

Age
11 to 14
Challenge level
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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?
Pattern Snake
problem

Pattern Snake

Age
11 to 14
Challenge level
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This pattern repeats every 12 dots. Can you work out what a later piece will be?
Hexagon Line
problem

Hexagon Line

Age
11 to 14
Challenge level
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How many hexagons are required for the perimeter of the whole shape to have length 1002cm?
Frogs
problem
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Frogs

Age
11 to 14
Challenge level
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How many moves does it take to swap over some red and blue frogs? Do you have a method?
Knights and Knaves
problem

Knights and Knaves

Age
11 to 14
Challenge level
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Knights always tell the truth. Knaves always lie. Can you catch these knights and knaves out?
Sliding robot
problem

Sliding robot

Age
11 to 14
Challenge level
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A robot moves along the number line. Where will it be after 2011 slides?
Even Up
problem

Even Up

Age
11 to 14
Challenge level
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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?
Expanding Pattern
problem

Expanding Pattern

Age
11 to 14
Challenge level
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How many squares are needed to continue this pattern?
How many Rectangles?
problem

How many Rectangles?

Age
11 to 14
Challenge level
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By drawing 5 horizontal and four vertical lines, one can form 12 rectangles. What is the greatest number of rectangles that can be formed by drawing 15 lines?
Picture Story
problem
Favourite

Picture Story

Age
14 to 16
Challenge level
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Can you see how this picture illustrates the formula for the sum of the first six cube numbers?
Series Sums
problem

Series Sums

Age
14 to 16
Challenge level
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Let S1 = 1 , S2 = 2 + 3, S3 = 4 + 5 + 6 ,........ Calculate S17.
Double Trouble
problem
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Double Trouble

Age
14 to 16
Challenge level
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Simple additions can lead to intriguing results...
Attractive Tablecloths
problem
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Attractive Tablecloths

Age
14 to 16
Challenge level
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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?
Collatz 13
problem

Collatz 13

Age
14 to 16
Challenge level
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If a number is even, halve it; if odd, treble it and add 1. If a sequence starts at 13, what will be the value of the 2008th term?
Ordered Sums
problem

Ordered Sums

Age
14 to 16
Challenge level
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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.
Collatz-ish
problem

Collatz-ish

Age
14 to 16
Challenge level
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A sequence is generated using these rules. For which values of n is the nth term equal to n?
Painted Cube
problem
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Painted Cube

Age
14 to 16
Challenge level
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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?
Trolley Park
problem

Trolley Park

Age
14 to 16
Challenge level
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In a supermarket, there are two lines of tightly packed trolleys. What is the length of one trolley?
12345
problem

12345

Age
14 to 16
Challenge level
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Repeat a pattern of numbers to form a larger number. Can you find the sum of all the digits?
Diagonals
problem

Diagonals

Age
14 to 16
Challenge level
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How many diagonals does a regular icosagon (20 sides) have?
Below 400
problem

Below 400

Age
14 to 16
Challenge level
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Can you work out which number will appear directly below 400 in this pattern?
Placeholder: several colourful numbers
problem

Difference Sequence

Age
14 to 16
Challenge level
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When will 2000 appear in this sequence?
Alternating Sum
problem

Alternating Sum

Age
14 to 16
Challenge level
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Given that the number 2008 is the correct answer to a sum, can you find n?
Mystic Rose
problem
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Mystic Rose

Age
14 to 16
Challenge level
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Use the animation to help you work out how many lines are needed to draw mystic roses of different sizes.
Partly Painted Cube
problem
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Partly Painted Cube

Age
14 to 16
Challenge level
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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
problem
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A little light thinking

Age
14 to 16
Challenge level
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Here is a machine with four coloured lights. Can you make two lights switch on at once? Three lights? All four lights?

Newspaper Sheets
problem

Newspaper Sheets

Age
14 to 16
Challenge level
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From only the page numbers on one sheet of newspaper, can you work out how many sheets there are altogether?
Steel Cables
problem
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Steel Cables

Age
14 to 16
Challenge level
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Some students have been working out the number of strands needed for different sizes of cable. Can you make sense of their solutions?