Copyright © University of Cambridge. All rights reserved.

'Weekly Problem 52 - 2010' printed from http://nrich.maths.org/

Show menu


Leonard writes down a sequence of numbers. After the first two numbers, each number is the sum of the previous two numbers in the sequence. The fourth number is $6$ and the sixth number is $15$. What is the seventh number in the sequence?
 
 
If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas. 
 
 

This problem is taken from the UKMT Mathematical Challenges.

View the previous week's solution
View the current weekly problem