Abstract
We discuss one-dimensional reversible cellular automata F ×3 and F ×3/2 that multiply numbers by 3 and 3/2, respectively, in base 6. They have the property that the orbits of all non-uniform 0-finite configurations contain as factors all finite words over the state alphabet {0,1,…,5}. Multiplication by 3/2 is conjectured to even have an orbit of 0-finite configurations that is dense in the usual product topology. An open problem by K. Mahler about Z-numbers has a natural interpretation in terms the automaton F ×3/2. We also remark that the automaton F ×3 that multiplies by 3 can be slightly modified to simulate the Collatz function. We state several open problems concerning pattern generation by cellular automata.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Ulam, S.: A Collection of Mathematical Problems. Interscience, New York, NY, USA (1960)
Kari, J.: Universal pattern generation by cellular automata. Theoretical Computer Science 429, 180–184 (2012)
Mahler, K.: An unsolved problem on the powers of 3/2. Journal of The Australian Mathematical Society 8, 313–321 (1968)
Lagarias, J.: The 3x + 1 problem and its generalizations. Amer. Math. Monthly 92, 3–23 (1985)
Kari, J.: Theory of cellular automata: A survey. Theor. Comput. Sci. 334, 3–33 (2005)
Wolfram, S.: A New Kind of Science. Wolfram Media (2002)
Blanchard, F., Maass, A.: Dynamical properties of expansive one-sided cellular automata. Israel Journal of Mathematics 99, 149–174 (1997)
Rudolph, D.J.: ×2 and ×3 invariant measures and entropy. Ergodic Theory and Dynamical Systems 10, 395–406 (1990)
Furstenberg, H.: Disjointness in ergodic theory, minimal sets, and a problem in diophantine approximation. Theory of Computing Systems 1, 1–49 (1967)
Wey, H.: Über die gleichverteilung von zahlen modulo eins. Math. Ann. 77, 313–352 (1916)
Cloney, T., Goles, E., Vichniac, G.Y.: The 3x+1 problem: A quasi cellular automaton. Complex Systems 1, 349–360 (1987)
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2012 Springer-Verlag Berlin Heidelberg
About this paper
Cite this paper
Kari, J. (2012). Cellular Automata, the Collatz Conjecture and Powers of 3/2. In: Yen, HC., Ibarra, O.H. (eds) Developments in Language Theory. DLT 2012. Lecture Notes in Computer Science, vol 7410. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-31653-1_5
Download citation
DOI: https://doi.org/10.1007/978-3-642-31653-1_5
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-642-31652-4
Online ISBN: 978-3-642-31653-1
eBook Packages: Computer ScienceComputer Science (R0)