Copyright © University of Cambridge. All rights reserved.

When is the value of the product $$(1 + {1 \over 2})(1 + {1 \over 3})(1 + {1 \over 4})...(1 + {1 \over n})$$ 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.*

View the current weekly problem