Starter quiz
- Which of these are triangular numbers?
- 1 ✓
- 8
- 12
- 15 ✓
- 21 ✓
-
- Which of these are prime numbers?
- 1
- 2 ✓
- 11 ✓
- 13 ✓
- 15
-
- 7, 8, 15, 23, 38 ... are the first five terms of a sequence. Which of these could be a rule for the sequence?
- Add 1, add 3, add 5 and so on, differences increasing by 2 each time.
- Add 1, add 7, add 13 and so on, differences increasing by 6 each time.
- Add the two previous terms to get the next term. ✓
- Multiply the two previous terms to get the next term.
- Multiply the previous term by 2 and subtract 1 to get the next term.
-
- A linear sequence starts -4, 6, ... . The next term is ______.
- '16' ✓
- A geometric sequence starts -4, 6, ... . What is the next term?
-
- ✓
-
-
-
-
- Which of these could be the first 5 terms in a sequence with a common second difference?
- 27, 64, 125, 216, 343, ...
- 28, 36, 45, 55, 66, ... ✓
- 30, 52, 76, 98, 122, ...
- 32, 48, 72, 108, 162, ...
- 36, 49, 64, 81, 100, ... ✓
-
Exit quiz
- Which of these could be a rule for generating the sequence 8, 16, 32, ...?
- Multiply the previous term by 2 to get the next term. ✓
- Add 8 to the previous term to get the next term.
- Add 8, then add 16 then add 24; common second difference of 8. ✓
- Add the two prevous terms to get the next term.
-
- Izzy says the next term in the sequence 1, 3, 6, 10, ... must be 15. Why is she incorrect?
- These are a triangular numbers, they are not a sequence.
- There is not a common difference of 5 between successive terms.
- The pattern may change after the fourth term. ✓
- Sequences must have a constant additive or multiplicative rule.
-
- Which of these could be a rule for the sequence: 37, 41, 43, 47, 53, ...?
- Prime numbers over 30 written in ascending order ✓
- A sequence which alternates between adding 4 and adding 2
- A linear sequence with common difference +4
- Sequence of numbers one more than the square numbers
- Integers where the digits sum to multiples of 5
-
- Which of these could be the rule for the sequence starting 17, 19, 20, ...?
- Odd numbers greater than 15.
- Add 2, add 1, add 0, add -1; common second difference of -1. ✓
- Integers greater than 16 where the digits sum to even numbers. ✓
- Numbers with nine letters when written in English.
- Add the two previous numbers and subtract 10 to get the next number.
-
- Which of these could be the rule for the sequence starting 6, 7, 9, ...?
- Linear sequence with a common difference of +2
- Sequence which adds 1, then 2, then 3; common second difference of 1 ✓
- Double the previous term then subtract 5 to get the next term ✓
- Number of letters in the English words for days of the week, starting on Monday ✓
- Number of letters in the English words for the months starting on August
-
- Match each sequence which start with the terms 3, 6, ... to the correct rule.
- 3, 6, 9, 12, ...⇔add 3 to the previous term to get the next term. ✓
- 3, 6, 12, 24, ...⇔multiply the previous term by 2 to get the next term. ✓
- 3, 6, 10, 15, ...⇔triangular numbers greater than 1. ✓
- 3, 6, 12, 21, ...⇔add 3, add 6, add 9, common second difference of 3. ✓
- 3, 6, 15, 42, ...⇔triple the previous term and subtract 3 to get the next term. ✓
Worksheet
Loading worksheet ...
Presentation
Loading presentation ...
Lesson Details
Key learning points
- There are more sequences than the ones seen so far.
- A numerical sequence is just a set of numbers often following a rule.
- If you only see a few of the terms, it is possible to incorrectly deduce the rule.
Common misconception
Sequences are either arithmetic or geometric.
There are many ways sequences can be generated and you can usually find more than one rule than can fit the first few terms of a sequence. Exploring these will ensure pupils don't have a narrow experience of sequences.
Keywords
Arithmetic/linear sequence - An arithmetic (or linear) sequence is a sequence where the difference between successive terms is constant.
Geometric sequence - A geometric sequence is a sequence with a constant multiplicative relationship between successive terms.
+