Maths Olympiad Prep

Library / CEMC Fermat /441 of 566

CEMC Fermat, 2003

Number theory Difficulty 3.0 AMC 10/12 Find the answer Canada

A sequence of numbers has 6 as its first term, and every term after the first is defined as follows: If a term, tt, is even, the next term in the sequence is 12t\frac{1}{2}t. If a term, ss, is odd, the next term is 3s+13s+1. Thus, the first four terms in the sequence are 6, 3, 10, 5. The 100th term is

(A) 11 (B) 22 (C) 33 (D) 44 (E) 66

We don't reproduce this publisher's solutions. Their own solution is here — work the problem first.
Want a route through all this instead of an archive? The track puts 2,604 problems in a working order, from Junior Challenge level to the IMO shortlist.

Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project. Solutions are the publisher's, linked not copied.