206, 103, 155, 233, 350, 175, 263, 395, 593, 890, 445, 668, 334, 167, 251, 377, 566, 283, 425, 638, 319, 479, 719, 1079, 1619, 2429, 3644, 1822, 911, 1367, 2051, 3077, 1616, 2308, 1154, 577, 866, 433, 650, 325, 488, 244, 122, 61, 92, 46, 23, 35, 53, 80, 40, 20, 10, 5, 8, 4, 2 〉. Using <strong>the</strong> trajectory, we can obtain <strong>the</strong> parity vector <strong>of</strong> an integer. Simply put, <strong>the</strong> entries <strong>of</strong> <strong>the</strong> parity vector are <strong>the</strong> elements <strong>of</strong> <strong>the</strong> trajectory reduced mod 2. We used <strong>the</strong> notation P n (x) to denote <strong>the</strong> first n elements <strong>of</strong> <strong>the</strong> parity vector <strong>of</strong> x. We will call this <strong>the</strong> partial parity vector <strong>of</strong> length n. For example, P 10 (11) = 〈1, 1, 0, 1, 0, 0, 1, 0, 0, 0〉. The total stopping time σ ∞ (x) <strong>of</strong> a positive integer x is defined to be <strong>the</strong> number <strong>of</strong> iterations needed for that integer to reach one, or ∞ if <strong>the</strong> trajectory <strong>of</strong> x does not contain one. In Chapter 2 we investigate <strong>the</strong> total stopping time through <strong>the</strong> construction <strong>of</strong> a graphical representation <strong>of</strong> <strong>the</strong> function, which is called a tree. This tree is based upon <strong>the</strong> inverse map <strong>of</strong> our function and helps us visualize <strong>the</strong> function. It also led us to identify several patterns found throughout <strong>the</strong> integer trajectories. In Chapter 5, we define a run to be a set <strong>of</strong> consecutive integers that all have <strong>the</strong> same total stopping time. In order to study <strong>the</strong>se runs we look at some special parity sequences known as blocks, strings and stems. We will define corresponding stems to be a pair <strong>of</strong> parity sequences <strong>of</strong> length k such that if two consecutive integers have parity vectors that begin with this pair, <strong>the</strong>n after k iterations, <strong>the</strong>ir trajectories merge. See Definition 1 in Chapter 3 for a precise definition. On <strong>the</strong> o<strong>the</strong>r hand, we will define corresponding blocks and corresponding 8
strings to be pairs <strong>of</strong> parity sequences <strong>of</strong> length k such that if two consecutive integers have parity vectors that begin with this pair, <strong>the</strong>n after k iterations <strong>the</strong> next entries in <strong>the</strong>ir trajectories are consecutive. See Definitions 2 and 4 in Chapter 4 for fur<strong>the</strong>r explanation. We use <strong>the</strong>se parity sequences as a tool for investigating <strong>the</strong> behavior <strong>of</strong> <strong>the</strong> 3x + 1 function, including finding long runs <strong>of</strong> consecutive integers. Finally, in Chapter 6, we discuss what <strong>the</strong> future might hold for fur<strong>the</strong>r research on <strong>the</strong> total stopping times <strong>of</strong> <strong>the</strong> <strong>Collatz</strong> <strong>Conjecture</strong>. 9
- Page 1 and 2: Explorations of the Collatz Conject
- Page 3 and 4: Dedication This project is dedicate
- Page 5 and 6: Preface It all began as a research
- Page 7 and 8: 6 Future Work 45 A Branch Count Pro
- Page 9: search. Most of my work, however is
- Page 13 and 14: Figure 2.1: 3x + 1 Tree integer. On
- Page 15 and 16: Table 2.1: Total Stopping Times σ
- Page 17 and 18: as stems. s i = 0 11...1 01 or s
- Page 19 and 20: Now, if we look at the case where x
- Page 21 and 22: 3.1 Applying Garner’s Stems In th
- Page 23 and 24: Then T 0 (T i+1 (m + 1)) = 3T i+1 (
- Page 25 and 26: Chapter 4 Blocks and Strings In the
- Page 27 and 28: is an integer if and only if P k (y
- Page 29 and 30: Definition 4. A string is a pair of
- Page 31 and 32: 4.2 Block and String Structure Sinc
- Page 33 and 34: Therefore, v and v ′ are block or
- Page 35 and 36: Then, v ′ = 〈v 1 , v 2 , ...v a
- Page 37 and 38: We can use Lemma 7, Equation 3.1, T
- Page 39 and 40: Since, 2 k ∆ = 2 k − 3 n , 3 k
- Page 41 and 42: 2 = 2 k − 2 r 1 1 = 2 k−1 − 2
- Page 43 and 44: Chapter 5 Long Runs of Consecutive
- Page 45 and 46: can be appended to the sequence in
- Page 47 and 48: Chapter 6 Future Work Throughout th
- Page 49 and 50: Appendix A Branch Count Procedure b
- Page 51: Bibliography [1] David Applegate an