Copyright © University of Cambridge. All rights reserved.

A sequence of positive integers $t_{1},t_{2}, t_{3}, t_{4}, ...$ is defined by:

$t_{1}=13$

$t_{n+1}=\frac{1}{2}t_{n}$ if $t_{n}$ is even

$t_{n+1}=3t_{n}+1$ if $t_{n}$ is odd.

What is the value of $t_{2008}$?

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 archive of all weekly problems grouped by curriculum topic*

View the current weekly problem