Copyright © University of Cambridge. All rights reserved.

'Producing an Integer' printed from http://nrich.maths.org/

Show menu

See all short problems arranged by curriculum topic in the short problems collection

When is the value of the product $$\left(1 + {1 \over 2}\right)\left(1 + {1 \over 3}\right)\left(1 + {1 \over 4}\right)...\left(1 + {1 \over n}\right)$$ equal to an integer?


 
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.